The multi-indexed partitional. - S. A. Joni (Discret. Math., 1979)

A Vector Space Analog of Permutations with Restricted Position. - S. A. Joni; Gian-Carlo Rota (J. Comb. Theory A, 1980)

From sets to functions: Three elementary examples. - S. A. Joni; Gian-Carlo Rota; Bruce E. Sagan (Discret. Math., 1981)

Umbralized Umbral Operators. - S. A. Joni (Eur. J. Comb., 1981)