> For the complete documentation index, see [llms.txt](https://open-carbon-protocol.gitbook.io/ocp-handbook/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://open-carbon-protocol.gitbook.io/ocp-handbook/registry.md).

# REGISTRY

- [Credit Issuance, Transfer, Retirement](https://open-carbon-protocol.gitbook.io/ocp-handbook/registry/credit-issuance-transfer-retirement.md)
- [Credit Cancellation](https://open-carbon-protocol.gitbook.io/ocp-handbook/registry/credit-cancellation.md)
- [Opening and Closing an Account](https://open-carbon-protocol.gitbook.io/ocp-handbook/registry/opening-and-closing-an-account.md)
- [Registry Schema and Infrastructure](https://open-carbon-protocol.gitbook.io/ocp-handbook/registry/registry-schema-and-infrastructure.md)
- [Certifications and Labels](https://open-carbon-protocol.gitbook.io/ocp-handbook/registry/certifications-and-labels.md)
- [CCP (Core Carbon Principles)](https://open-carbon-protocol.gitbook.io/ocp-handbook/registry/certifications-and-labels/ccp-core-carbon-principles.md)
- [CORSIA](https://open-carbon-protocol.gitbook.io/ocp-handbook/registry/certifications-and-labels/corsia.md)