The three quantum numbers

Atomic Mass (A)
Hypercharge (Y)
Isotopic Spin (I)

Chew, Geoffrey F./ Gell-Mann, Murray/ Rosenfeld, Arthur H. (1964). Strongly Interacting Particles. Scientific American, Inc. S.83.

We are now ready to describe how the five quantum numbers can provide the basis for a new naming system. By appropriate selection of three of the five quantum numbers we can indicate immediately whether a strongly interacting particle is a baryon or a meson, how many members it has in its immediate family (that is, its multiplicity) and what its degree of strangeness is. The three quantum numbers that provide this information are the atomic mass, or baryon, number A, the hypercharge Y and the isotopic spin I. (It will be recalled that Y is directly related to strangeness and I to multiplicity.)