Guts Muths, J. C. F., & Salzmann, C. G. (1803). Gymnastics for youth, or A practical guide to healthful and amusing exercises for the use of schools. An essay toward the necessary improvement of education, chiefly as it relates to the body. Philadelphia: Printed for P. Byrne.

Guts Muths, Johann Christoph Friedrich, and Christian Gotthilf Salzmann. Gymnastics for Youth, or A Practical Guide to Healthful and Amusing Exercises for the Use of Schools. An Essay Toward the Necessary Improvement of Education, Chiefly As It Relates to the Body. Philadelphia: Printed for P. Byrne, 1803.

Guts Muths, Johann Christoph Friedrich, and Christian Gotthilf Salzmann. Gymnastics for Youth, or A Practical Guide to Healthful and Amusing Exercises for the Use of Schools. An Essay Toward the Necessary Improvement of Education, Chiefly As It Relates to the Body. Philadelphia: Printed for P. Byrne, 1803.