Gaya APA
Laer, P, V. (1953).
Philosophico-scientific problems. Transl. by H.J. Koren. .
Pittsburgh:
Duquesne University Press.
Gaya MLA
Laer, P.H., Van.
"Philosophico-scientific problems. Transl. by H.J. Koren. ".
Pittsburgh:
Duquesne University Press,
1953.
Buku.