Zwarg, L. F. (1923). Apparatus work for boys and girls: A course of graded instruction, with illustrations in the use of horizontal bars, parallel bars, horses, rings, ladders, stall bars, giant strides, climbing poles, bucks, mats. J. J. McVey.
Chicago Style (17th ed.) CitationZwarg, Leopold Fredrick. Apparatus Work for Boys and Girls: A Course of Graded Instruction, with Illustrations in the Use of Horizontal Bars, Parallel Bars, Horses, Rings, Ladders, Stall Bars, Giant Strides, Climbing Poles, Bucks, Mats. Philadelphia, Pa.: J. J. McVey, 1923.
MLA (9th ed.) CitationZwarg, Leopold Fredrick. Apparatus Work for Boys and Girls: A Course of Graded Instruction, with Illustrations in the Use of Horizontal Bars, Parallel Bars, Horses, Rings, Ladders, Stall Bars, Giant Strides, Climbing Poles, Bucks, Mats. J. J. McVey, 1923.