1. F. Gross, Complex analysis, Lecture Notes in Math., vol. 599, Springer, Berlin and New York, 1977 pp. 51–69
2. On preimage and range sets of meromorphic functions;Gross, Fred;Proc. Japan Acad. Ser. A Math. Sci.,1982
3. F. Gross, Factorizations of meromorphic functions, U.S. Government Printing Office Publication, Washington D.C., 1972.
4. On the characteristic of functions meromorphic in the unit disk and of their integrals;Hayman, W. K.;Acta Math.,1964
5. On deficiencies of differential polynomials. II;Yang, Chung Chun;Math. Z.,1972