Lee, Jae-Woo, Multiple Stellar Populations of Globular Clusters from Homogeneous Ca–CN–CH Photometry. V. cn′JWL as a Surrogate cnJWL Index and NGC 6723, The Astrophysical Journal, 2019, 883 (2): 166, S2CID 201070324, arXiv:1908.06670, doi:10.3847/1538-4357/ab3d34
Lee, Jae-Woo, Multiple Stellar Populations of Globular Clusters from Homogeneous Ca–CN–CH Photometry. V. cn′JWL as a Surrogate cnJWL Index and NGC 6723, The Astrophysical Journal, 2019, 883 (2): 166, S2CID 201070324, arXiv:1908.06670, doi:10.3847/1538-4357/ab3d34
harvard.edu
ui.adsabs.harvard.edu
Shapley, Harlow; Sawyer, Helen B., A Classification of Globular Clusters, Harvard College Observatory Bulletin, August 1927, 849 (849): 11–14, Bibcode:1927BHarO.849...11S.
Lee, Jae-Woo, Multiple Stellar Populations of Globular Clusters from Homogeneous Ca–CN–CH Photometry. V. cn′JWL as a Surrogate cnJWL Index and NGC 6723, The Astrophysical Journal, 2019, 883 (2): 166, S2CID 201070324, arXiv:1908.06670, doi:10.3847/1538-4357/ab3d34