MLA

Haldeman-Julius, E. (Emanuel), 1888-1951, Harvey, Alexander, Sophocles. Little blue book. c1924. https://collections.library.yale.edu/catalog/10800586.

APA, 6th edition

Haldeman-Julius, E. (Emanuel), 1888-1951, & Harvey, Alexander, & Sophocles. (c1924)[Little blue book]. https://collections.library.yale.edu/catalog/10800586.