“Thirteen-Color Photometry of Subdwarf Stars. II. Calibration of the 37-45 Excess Using Spectroscopic (Fe H) Stars Abundances”. Revista Mexicana De Astronomía Y Astrofísica, vol. 4, no. 1, Jan. 1978, pp. 301-5, https://astronomia.unam.mx/journals/rmxaa/article/view/1979rmxaa. 4. 301s.