APA

National Education Association of the United States. Department of Elementary School Principals, . (1960). Those first school years. Washington: National Education Association.

Chicago

National Education Association of the United States. Department of Elementary School Principals, . 1960. Those first school years. Washington: National Education Association.

Harvard

National Education Association of the United States. Department of Elementary School Principals, . (1960). Those first school years. Washington: National Education Association.

MLA

National Education Association of the United States. Department of Elementary School Principals, . Those first school years. Washington: National Education Association. 1960.