The words "usual" and "customary" mean "according to usage".
N.D. Cent. Code § 1-01-32
Usual and customary - Definition
Known as the North Dakota Century Code
The act spans §§ 1–1 (54 sections).
Official source: North Dakota Legislative Branch. Reproduced from public-domain North Dakota statutes; confirm against the official source for the current text. Not legal advice.