Moesgaard, Kristian P. (1973). «Copernican influence on Tycho Brahe». En Jerzy Dobrzycki, ed. The reception of Copernicus' heliocentric theory: proceedings of a symposium organized by the Nicolas Copernicus Committee of the International Union of the History and Philosophy of Science. Toruń, Poland: Studia Copernicana, Springer. ISBN90-277-0311-6.
Johnson, H. L; Morgan, W. W (1953). «Fundamental stellar photometry for standards of spectral type on the Revised System of the Yerkes Spectral Atlas». The Astrophysical Journal117: 313. Bibcode:1953ApJ...117..313J. doi:10.1086/145697.
Odell, A. P (1980). «The structure of Alpha Virginis. III - the pulsation characteristics». The Astrophysical Journal236: 536. Bibcode:1980ApJ...236..536O. doi:10.1086/157771.
Johnson, H. L; Morgan, W. W (1953). «Fundamental stellar photometry for standards of spectral type on the Revised System of the Yerkes Spectral Atlas». The Astrophysical Journal117: 313. Bibcode:1953ApJ...117..313J. doi:10.1086/145697.
Odell, A. P (1980). «The structure of Alpha Virginis. III - the pulsation characteristics». The Astrophysical Journal236: 536. Bibcode:1980ApJ...236..536O. doi:10.1086/157771.