APA (7th ed.) Citation
Schouten, J. A., & Kulk, W. v. d. (1949). Pfaff's problem and its generalizations. Clarendon Press.
Chicago Style (17th ed.) Citation
Schouten, Jan Arnoldus, and Wouter van der Kulk. Pfaff's Problem and Its Generalizations. Oxford: Clarendon Press, 1949.
MLA (9th ed.) Citation
Schouten, Jan Arnoldus, and Wouter van der Kulk. Pfaff's Problem and Its Generalizations. Clarendon Press, 1949.
Warning: These citations may not always be 100% accurate.