R. E. Langer

Orbit theory : [proceedings of the Ninth Symposium in Applied Mathematics of the American Mathematical Society, held at New York University, April 4-6, 1957

Garrett Birkhoff, R. E. Langer, 1959 .

Partial Differential Equations and Continuum Mechanics.

R. E. Langer, John McNamee, 1962 .

An inverse problem in differential equations

R. E. Langer, R. Langer, 1933 .