APA
Koos L. V., . (1955). Junior high school trends. New York: Harper & Brothers.
Chicago
Koos Leonard V, . 1955. Junior high school trends. New York: Harper & Brothers.
Harvard
Koos L. V., . (1955). Junior high school trends. New York: Harper & Brothers.
MLA
Koos Leonard V, . Junior high school trends. New York: Harper & Brothers. 1955.