Johnston, E. G. (1930). Point systems and awards: The guidance, stimulation and limitation of pupil participation. A.S. Barnes and company, incorporated.
Chicago Style aipamenaJohnston, Edgar Grant. Point Systems and Awards: The Guidance, Stimulation and Limitation of Pupil Participation. New York: A.S. Barnes and company, incorporated, 1930.
MLA aipamenaJohnston, Edgar Grant. Point Systems and Awards: The Guidance, Stimulation and Limitation of Pupil Participation. A.S. Barnes and company, incorporated, 1930.
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