Dirichlet's principle, conformal mapping, and minimal surfaces. - Interscience Publishers, 1950. - (Pure and Applied Mathematics - Interscience Publishers).
Convex polytopes. - Interscience Publishers, 1967. - (Pure and Applied Mathematics - Interscience Publishers; 16).
Combinatorial group theory : presentations of groups in terms of generators and relations. - Interscience Publishers, 1966. - (Pure and Applied Mathematics - Interscience Publishers; 13).
Representation theory of finite groups and associative algebras. - Interscience Publishers, 1962. - (Pure and Applied Mathematics - Interscience Publishers; 11).
Lectures on differential and integral equations. - Interscience Publishers, 1960. - (Pure and Applied Mathematics - Interscience Publishers; 10).
Orthogonal functions. - Interscience Publishers, 1959. - (Pure and Applied Mathematics - Interscience Publishers; 9).
Linear operators, Part III: spectral operators. - Interscience Publishers, 1971. - (Pure and Applied Mathematics - Interscience Publishers; 7).
Linear operators, Part II: spectral theory, self adjoint operators in Hilbert space. - Interscience Publishers, 1963. - (Pure and Applied Mathematics - Interscience Publishers; 7).
Linear operators, Part I: general theory. - Interscience Publishers, 1957. - (Pure and Applied Mathematics - Interscience Publishers; 7).
Differential equations: geometric theory. - Interscience Publishers, 1957. - (Pure and Applied Mathematics - Interscience Publishers; 6).
Nonlinear vibrations, in mechanical and electrical systems. - Interscience Publishers, 1950. - (Pure and Applied Mathematics - Interscience Publishers; 2).