APA (7th ed.) Citation

Geeslin, R. H. (1971). The "Graded Difficulty" Library.

Chicago Style (17th ed.) Citation

Geeslin, Robert H. The "Graded Difficulty" Library. 1971.

MLA (9th ed.) Citation

Geeslin, Robert H. The "Graded Difficulty" Library. 1971.

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