1. OCEG. (2021). GRC Capability Model ("The Red Book"), Version 3.5.
Section 2.2.3, The Outcome of Principled Performance: "Compliance is the state of adherence to the organization’s mandatory and voluntary obligations." This directly links the concept of compliance to meeting obligations.
Glossary, Page 113: Defines "Compliance" as "Act of adhering to, and the ability to demonstrate adherence to, mandatory requirements and voluntary commitments."
Glossary, Page 116: Defines "Obligation" as "A requirement that an organization must, or chooses to, meet."
2. Racz, N., Weippl, E., & Seufert, A. (2010). A frame of reference for research of integrated Governance, Risk, & Compliance (GRC). Proceedings of the 43rd Hawaii International Conference on System Sciences.
Section 3.2, GRC Definitions: The paper, referencing OCEG, discusses compliance as being concerned with conforming to stated requirements (obligations), distinguishing it from risk management (addressing uncertainty) and governance (steering the organization). (DOI: https://doi.org/10.1109/HICSS.2010.374)