TY - DATA AU - M. Arkowitz AU - C.R. Curjel TI - Groups of Homotopy Classes T2 - Lecture Notes in Mathematics SN - 9783662159132 PY - 1964/// CY - Heidelberg PB - Springer Berlin KW - Mathematics and Statistics UR - https://doi.org/10.1007/978-3-662-15913-2 ER -