APA (7th ed.) Citation

Internacional, S. E. P. d. l. R. B., & Biheller, F. Letter.

Chicago Style (17th ed.) Citation

Internacional, Spain. Ejército Popular de la República. Brigada, and Frico Biheller. Letter.

MLA (8th ed.) Citation

Internacional, Spain. Ejército Popular de la República. Brigada, and Frico Biheller. Letter.

Warning: These citations may not always be 100% accurate.