Early Plains Wars, Gratian, Sully, Mankato, Etc.
MLA
Erdoes, Richard, 1912-2008. Early Plains Wars, Gratian, Sully, Mankato, Etc.. Box 45 | Plains Indian History I. 1976, undated. https://collections.library.yale.edu/catalog/10256186.
APA, 6th edition
Erdoes, Richard, 1912-2008. (["Box 45 | Plains Indian History I"])(1976, undated)[Early Plains Wars, Gratian, Sully, Mankato, Etc.]. https://collections.library.yale.edu/catalog/10256186.