Finiteness of bound states of general n -body operators Evans, W. D.; Lewis, R.; Saitó, Y. — 1990 Equadiff 7
The dimensions of complemented hilbertian subspaces of uniformly convex Banach lattices D. R. Lewis — 1983 Compositio Mathematica
On the number of bound states of a bosonic N-particle Coulomb system. V. Bach; R. Lewis; E.H. Lieb — 1993 Mathematische Zeitschrift