1678 — Edward Phillips, The new world of English words: or, a new general dictionary, (first ed. 1658)
Cardinal numerals, are those which express the number of things.
1808, William Neilson, An Introduction to the Irish Language, page 103
In speaking of the succession of kings, and the like, the cardinal numeral is rather used than the ordinal; as, Seoirse an tri, George the third; rather than Seoirse an treas.
1872 — Richard Morris, Historical outlines of English accidence, p.110
Numbers may be considered under their divisions — Cardinal, Ordinal, and Indefinite Numerals.
1993 — William W. Derbyshire, A Basic Reference Grammar of Slovene (Columbus, Ohio: Slavica Publishers, Inc.), p.56
The cardinal numeral ‘one’ occurs in the singular and is declined like bogàt.
2002 — Laurie Bauer & Rodney Huddleston, "Lexical word-formation", p1621-1722 in The Cambridge Grammar of the English Language, p1716
Numerals cut across the division between syntax and morphology: cardinal numerals expressing numbers below 100 are single words, while those expressing higher numbers are syntactically composite.
2005 — F. M. Wheelock, Wheelock’s Latin, 6th ed. revised (New York: Harper Resources, 2005), p.97
In Latin most cardinal numerals through 100 are indeclinable adjectives.