APA (7th ed.) Citation

Shapley, H., Shapley, H., & Richmond, M. L. (1921). Studies based on the colors and magnitudes in stellar clusters (Reprinted from the "Astrophysical journal", T. LIV, 1921.). s.t.

Chicago Style (17th ed.) Citation

Shapley, Harlow, Harlow Shapley, and Myrtle L. Richmond. Studies Based on the Colors and Magnitudes in Stellar Clusters. Reprinted from the "Astrophysical journal", T. LIV, 1921. Washington: s.t, 1921.

MLA (9th ed.) Citation

Shapley, Harlow, et al. Studies Based on the Colors and Magnitudes in Stellar Clusters. Reprinted from the "Astrophysical journal", T. LIV, 1921. s.t, 1921.