APA

Willkie H. F., Kolachov P. J. & Indiana Farm Bureau. (1943). Llamado a la meditacion: carburante agricola (Food for thought). Indianapolis, Indiana: Indiana Farm Bureau, Inc.

Chicago

Willkie Herman Frederick, Kolachov Paul John and Indiana Farm Bureau. 1943. Llamado a la meditacion: carburante agricola (Food for thought). Indianapolis, Indiana: Indiana Farm Bureau, Inc.

Harvard

Willkie H. F., Kolachov P. J. and Indiana Farm Bureau. (1943). Llamado a la meditacion: carburante agricola (Food for thought). Indianapolis, Indiana: Indiana Farm Bureau, Inc.

MLA

Willkie Herman Frederick, Kolachov Paul John and Indiana Farm Bureau. Llamado a la meditacion: carburante agricola (Food for thought). Indianapolis, Indiana: Indiana Farm Bureau, Inc. 1943.