1. Compute SHA-256 of OTSCanonicalRecord value → must equal OTSHash 2. Open OTSProofURL → extract Bitcoin block number → must equal OTSBitcoinBlock 3. GET OTSBitcoinBlockVerifyURL → returns the Bitcoin block hash at height OTSBitcoinBlock; GET https://blockstream.info/api/block/{that hash} → its timestamp must match OTSTimestamp 4. Read CopyrightID inside OTSCanonicalRecord → must equal the CopyrightID above 5. GET OTSVerificationAPI → pre-computed 6-check result from server 6. If all match: this entity was registered on CopyrightChains at OTSTimestamp, independently verifiable on Bitcoin
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xce6b7d504cec6ddb82659801b01504f5df6767eac5eefb7caf2f748a421d4b29. Chain 2 (Bitcoin): anchored in block 953423 (2026-06-12T21:20:00Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/d1cb5fc4-42e8-48b4-95e8-e421faa99dde.json and https://artists.proofprofile.net/proofs/artist/d1cb5fc4-42e8-48b4-95e8-e421faa99dde.ots, run `ots verify -f record.json proof.ots` (https://opentimestamps.org).
Englisch – Wortschatz für Anfänger A1,A2 (Englisch-Hörkurs für Anfänger und leicht Fortgeschrittene)
Englisch – Wortschatz für die Mittelstufe B1_Teil 01 (Englisch-Hörkurs für die Mittelstufe)
Kapitel 5.3 - Englisch – Wortschatz für die Mittelstufe B1_Teil 01
1. Confirm isrcCode identifies the recording in the pre-2022 source corpus and cc-db-prod record 2. GET OTSVerificationAPI → server-side canonical-record, hash, and attestation checks must pass 3. GET OTSBitcoinBlockVerifyURL → returns the Bitcoin block hash at height OTSBitcoinBlock; GET https://blockstream.info/api/block/{that hash} → its timestamp must match OTSTimestamp 4. Confirm CopyrightID is the CopyrightChains transaction hash 5. If all match: the cc-db-prod record is independently anchored on Bitcoin at OTSTimestamp
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x1f5c783636ea4c5b550683eb8850bf8b49ea050bf2c199f041c3a31b0b52e65e. Chain 2 (Bitcoin): anchored in block 958808 (2026-07-20T02:49:15Z), registered by our registry partner. The server verifies the private canonical record against OTSHash without exposing internal provider keys. Confirm the public ISRC, CopyrightID, and Bitcoin evidence via https://artists.proofprofile.net/api/v1/bot/ots/verify/track/DEWI52318385.
Kapitel 5.6 & Kapitel 6.1 - Englisch – Wortschatz für die Mittelstufe B1_Teil 01
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x43620b27c8f17d0bf515361b36ef8416e87601b85006a1020f2578946f07438a. Chain 2 (Bitcoin): anchored in block 956738 (2026-07-05T04:47:21Z), registered by our registry partner. The server verifies the private canonical record against OTSHash without exposing internal provider keys. Confirm the public ISRC, CopyrightID, and Bitcoin evidence via https://artists.proofprofile.net/api/v1/bot/ots/verify/track/DEWI52318388.
Englisch – Wortschatz für die Mittelstufe B1_Teil 02 (Englisch-Hörkurs für die Mittelstufe B1)
Technisches Englisch A1 - B1 (Technisches Englisch für Anfänger und Leichtvorgeschrittene)
Englisch - Wortschatz für Fortgeschrittene C1-C2
Englisch-Wortschatz für Fortgeschrittene B2
Kapitel 1 & Kapitel 2.1 - Englisch-Wortschatz für Fortgeschrittene B2
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xb01bff5c2d92abaa01170c5a9aace9d5a981dc31929463b27ba22a7ab14a3c5a. Chain 2 (Bitcoin): anchored in block 956857 (2026-07-06T01:26:17Z), registered by our registry partner. The server verifies the private canonical record against OTSHash without exposing internal provider keys. Confirm the public ISRC, CopyrightID, and Bitcoin evidence via https://artists.proofprofile.net/api/v1/bot/ots/verify/track/DEWI52320354.
Kapitel 2.2 & Kapitel 3.1 - Englisch-Wortschatz für Fortgeschrittene B2
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x13627573e18df49994d417fccc7391ad002080ed41f7678274da8e0f72671c3d. Chain 2 (Bitcoin): anchored in block 958703 (2026-07-19T08:36:12Z), registered by our registry partner. The server verifies the private canonical record against OTSHash without exposing internal provider keys. Confirm the public ISRC, CopyrightID, and Bitcoin evidence via https://artists.proofprofile.net/api/v1/bot/ots/verify/track/DEWI52320355.
Kapitel 3.2 & Kapitel 4.1 - Englisch-Wortschatz für Fortgeschrittene B2
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xdf9976579d0f9d143fd6eee57a41717e0307b8188f1244525d98f9ad43f1646e. Chain 2 (Bitcoin): anchored in block 956772 (2026-07-05T10:01:46Z), registered by our registry partner. The server verifies the private canonical record against OTSHash without exposing internal provider keys. Confirm the public ISRC, CopyrightID, and Bitcoin evidence via https://artists.proofprofile.net/api/v1/bot/ots/verify/track/DEWI52320356.
Kapitel 4.2 - Englisch-Wortschatz für Fortgeschrittene B2
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x4ed6f0864d36088ca697ae1b8b6541112fa9adb527e81912cab5a937658d4962. Chain 2 (Bitcoin): anchored in block 958951 (2026-07-21T04:02:11Z), registered by our registry partner. The server verifies the private canonical record against OTSHash without exposing internal provider keys. Confirm the public ISRC, CopyrightID, and Bitcoin evidence via https://artists.proofprofile.net/api/v1/bot/ots/verify/track/DEWI52320357.
Kapitel 4.3 & Kapitel 5.1 - Englisch-Wortschatz für Fortgeschrittene B2
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x738561f5ae8d66dd5726a63774de865f762afd868e4ac27204b99471e414ccec. Chain 2 (Bitcoin): anchored in block 958935 (2026-07-20T22:08:19Z), registered by our registry partner. The server verifies the private canonical record against OTSHash without exposing internal provider keys. Confirm the public ISRC, CopyrightID, and Bitcoin evidence via https://artists.proofprofile.net/api/v1/bot/ots/verify/track/DEWI52320358.
Kapitel 5.2 - Englisch-Wortschatz für Fortgeschrittene B2
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xb966602a7bf02fb2283fd5dc6671e7404d161e1ce5f5f920d1ad90a7721ffcc9. Chain 2 (Bitcoin): anchored in block 956738 (2026-07-05T04:47:21Z), registered by our registry partner. The server verifies the private canonical record against OTSHash without exposing internal provider keys. Confirm the public ISRC, CopyrightID, and Bitcoin evidence via https://artists.proofprofile.net/api/v1/bot/ots/verify/track/DEWI52320359.
Kapitel 5.3 - Englisch-Wortschatz für Fortgeschrittene B2
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xc0ead71f1e7fa4909f87c9ae61c3417b80160a2d24eeb1226d12424a2465282c. Chain 2 (Bitcoin): anchored in block 958489 (2026-07-18T04:13:26Z), registered by our registry partner. The server verifies the private canonical record against OTSHash without exposing internal provider keys. Confirm the public ISRC, CopyrightID, and Bitcoin evidence via https://artists.proofprofile.net/api/v1/bot/ots/verify/track/DEWI52320360.
Kapitel 5.4 - Englisch-Wortschatz für Fortgeschrittene B2
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x1d74a153be748653c92f140f71adb3221873644edc91152ec905d0f999758880. Chain 2 (Bitcoin): anchored in block 958823 (2026-07-20T04:29:18Z), registered by our registry partner. The server verifies the private canonical record against OTSHash without exposing internal provider keys. Confirm the public ISRC, CopyrightID, and Bitcoin evidence via https://artists.proofprofile.net/api/v1/bot/ots/verify/track/DEWI52320361.
Kapitel 5.5 & Kapitel 6.1 - Englisch-Wortschatz für Fortgeschrittene B2
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xa39812f1fb4fc622dbe1ac875800a7990c849f2fbd6826d5dc5725d9083c6e53. Chain 2 (Bitcoin): anchored in block 959058 (2026-07-21T23:50:18Z), registered by our registry partner. The server verifies the private canonical record against OTSHash without exposing internal provider keys. Confirm the public ISRC, CopyrightID, and Bitcoin evidence via https://artists.proofprofile.net/api/v1/bot/ots/verify/track/DEWI52320362.
Kapitel 6.2 - Englisch-Wortschatz für Fortgeschrittene B2
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x59baf5bea810ce9d61eb631ef93b534e966b8ec86a75e1ec4eed934bd59c74b1. Chain 2 (Bitcoin): anchored in block 958987 (2026-07-21T09:04:56Z), registered by our registry partner. The server verifies the private canonical record against OTSHash without exposing internal provider keys. Confirm the public ISRC, CopyrightID, and Bitcoin evidence via https://artists.proofprofile.net/api/v1/bot/ots/verify/track/DEWI52320363.
Kapitel 6.3 - Englisch-Wortschatz für Fortgeschrittene B2
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xc9c65889e6ca82a9b67e2f8ff87d1dbf028115663bc1d03bdbd51cb7801e15cc. Chain 2 (Bitcoin): anchored in block 959061 (2026-07-21T23:50:04Z), registered by our registry partner. The server verifies the private canonical record against OTSHash without exposing internal provider keys. Confirm the public ISRC, CopyrightID, and Bitcoin evidence via https://artists.proofprofile.net/api/v1/bot/ots/verify/track/DEWI52320364.
Kapitel 6.4 - Englisch-Wortschatz für Fortgeschrittene B2
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xb4280781f4500a7c71cbd871f98fba489cff456a32ed339dd4825bedbcafd4a8. Chain 2 (Bitcoin): anchored in block 958823 (2026-07-20T07:11:27Z), registered by our registry partner. The server verifies the private canonical record against OTSHash without exposing internal provider keys. Confirm the public ISRC, CopyrightID, and Bitcoin evidence via https://artists.proofprofile.net/api/v1/bot/ots/verify/track/DEWI52320365.
Kapitel 6.5 - Englisch-Wortschatz für Fortgeschrittene B2
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x3d09f851579d9a538f4dd7a77ad297af70b16da605e549dd89172438d9ccf6ee. Chain 2 (Bitcoin): anchored in block 958342 (2026-07-17T03:48:19Z), registered by our registry partner. The server verifies the private canonical record against OTSHash without exposing internal provider keys. Confirm the public ISRC, CopyrightID, and Bitcoin evidence via https://artists.proofprofile.net/api/v1/bot/ots/verify/track/DEWI52320366.
Kapitel 6.6 & Kapitel 7.1 - Englisch-Wortschatz für Fortgeschrittene B2
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x8a8c534d996f4dd0cde151fa01af99422696bf012da7f6b900c01b71b3580167. Chain 2 (Bitcoin): anchored in block 958742 (2026-07-19T16:12:15Z), registered by our registry partner. The server verifies the private canonical record against OTSHash without exposing internal provider keys. Confirm the public ISRC, CopyrightID, and Bitcoin evidence via https://artists.proofprofile.net/api/v1/bot/ots/verify/track/DEWI52320367.
Kapitel 7.2 - Englisch-Wortschatz für Fortgeschrittene B2
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x2ed14a92127919f6e257c36f122bf0967697b9330c444389c5ce422736ba5edc. Chain 2 (Bitcoin): anchored in block 958991 (2026-07-21T11:09:34Z), registered by our registry partner. The server verifies the private canonical record against OTSHash without exposing internal provider keys. Confirm the public ISRC, CopyrightID, and Bitcoin evidence via https://artists.proofprofile.net/api/v1/bot/ots/verify/track/DEWI52320368.
Kapitel 7.3 & Kapitel 8.1 - Englisch-Wortschatz für Fortgeschrittene B2
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x0bf3b5dc82b1609ec31d5e57fa776f972ad1c63292f05b740011525902c9b338. Chain 2 (Bitcoin): anchored in block 959100 (2026-07-22T07:41:01Z), registered by our registry partner. The server verifies the private canonical record against OTSHash without exposing internal provider keys. Confirm the public ISRC, CopyrightID, and Bitcoin evidence via https://artists.proofprofile.net/api/v1/bot/ots/verify/track/DEWI52320369.
Kapitel 8.2 - Englisch-Wortschatz für Fortgeschrittene B2
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x6c6c4ba1257f4592e66d44586c311637a4e40d6be92b0b2c5479bfb8227edc87. Chain 2 (Bitcoin): anchored in block 956826 (2026-07-05T19:27:56Z), registered by our registry partner. The server verifies the private canonical record against OTSHash without exposing internal provider keys. Confirm the public ISRC, CopyrightID, and Bitcoin evidence via https://artists.proofprofile.net/api/v1/bot/ots/verify/track/DEWI52320370.
Kapitel 10.2 - Englisch-Wortschatz für Fortgeschrittene B2
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xd31903dbc34c318a4e10293e06f6be727ac9e52dd7d7c057b2e59da7c0a27aaa. Chain 2 (Bitcoin): anchored in block 956822 (2026-07-05T18:48:28Z), registered by our registry partner. The server verifies the private canonical record against OTSHash without exposing internal provider keys. Confirm the public ISRC, CopyrightID, and Bitcoin evidence via https://artists.proofprofile.net/api/v1/bot/ots/verify/track/DEWI52320374.
Kapitel 10.3 & Kapitel 11.1 - Englisch-Wortschatz für Fortgeschrittene B2
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x8bf9b8983a5d161813a1986b2ce619211f6c93bd6cdf6bf8965ff156e67643bf. Chain 2 (Bitcoin): anchored in block 958700 (2026-07-19T08:09:50Z), registered by our registry partner. The server verifies the private canonical record against OTSHash without exposing internal provider keys. Confirm the public ISRC, CopyrightID, and Bitcoin evidence via https://artists.proofprofile.net/api/v1/bot/ots/verify/track/DEWI52320375.
English für den Urlaub A1-B1 (Audiokurs der Englischen Sprache für Reisende)
Kapitel 1 & Kapitel 2.1 - English für den Urlaub A1-B1
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x73097b1cce6dcf385fb05f2a633f6a61e5e733af2e3aa37c07439e8f891ace39. Chain 2 (Bitcoin): anchored in block 959058 (2026-07-21T23:39:31Z), registered by our registry partner. The server verifies the private canonical record against OTSHash without exposing internal provider keys. Confirm the public ISRC, CopyrightID, and Bitcoin evidence via https://artists.proofprofile.net/api/v1/bot/ots/verify/track/DEWI52319803.
Kapitel 2.2 & Kapitel 3.1 - English für den Urlaub A1-B1
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xb040238ef7b75c7049862158a9ed00ba3101e518e7bf15bb80eca12c879f8dbf. Chain 2 (Bitcoin): anchored in block 959024 (2026-07-21T15:31:18Z), registered by our registry partner. The server verifies the private canonical record against OTSHash without exposing internal provider keys. Confirm the public ISRC, CopyrightID, and Bitcoin evidence via https://artists.proofprofile.net/api/v1/bot/ots/verify/track/DEWI52319804.
Kapitel 4.3 & Kapitel 5.1 - English für den Urlaub A1-B1
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x46822859541bb8f159351a523d2cfd3e7aa26461ef2e5d96c915ec24d6b40384. Chain 2 (Bitcoin): anchored in block 958342 (2026-07-17T02:54:46Z), registered by our registry partner. The server verifies the private canonical record against OTSHash without exposing internal provider keys. Confirm the public ISRC, CopyrightID, and Bitcoin evidence via https://artists.proofprofile.net/api/v1/bot/ots/verify/track/DEWI52319808.
Kapitel 5.2 - English für den Urlaub A1-B1
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x8a236246be2af1561b1e13f791de601825453cc54da30a04ef6cfafa6c266878. Chain 2 (Bitcoin): anchored in block 958601 (2026-07-18T19:27:02Z), registered by our registry partner. The server verifies the private canonical record against OTSHash without exposing internal provider keys. Confirm the public ISRC, CopyrightID, and Bitcoin evidence via https://artists.proofprofile.net/api/v1/bot/ots/verify/track/DEWI52319809.
Inglés comercial A1- B1 (de nivel principiante a pre-intermedio)
Angličtina do práce A1-B1 (Kurz obchodnej angličtiny pre začiatočníkov a mierne pokročilých)