R.R. Bowker Company. Ulrich's International Peridiocals Directory. vol 1 a - m. R.R. Bower Company.
Cita Chicago (17th ed.)R.R. Bowker Company. Ulrich's International Peridiocals Directory. Vol 1 a - M. Nueva York: R.R. Bower Company.
Cita MLA (9th ed.)R.R. Bowker Company. Ulrich's International Peridiocals Directory. Vol 1 a - M. R.R. Bower Company.
Atenció: Aquestes cites poden no estar 100% correctes.