On proximate type of entire functions
Compositio Mathematica, Volume 18 (1967) no. 1-2, p. 7-12 
@article{CM_1967__18_1-2_7_0,
     author = {Srivastava, R. S. L. and Juneja, O. P.},
     title = {On proximate type of entire functions},
     journal = {Compositio Mathematica},
     publisher = {P. Noordhoff N. V., Groningen},
     volume = {18},
     number = {1-2},
     year = {1967},
     pages = {7-12},
     zbl = {0181.35301},
     mrnumber = {226021},
     language = {en},
     url = {http://www.numdam.org/item/CM_1967__18_1-2_7_0}
}

Srivastava, R. S. L.; Juneja, O. P. On proximate type of entire functions. Compositio Mathematica, Volume 18 (1967) no. 1-2, pp. 7-12. http://www.numdam.org/item/CM_1967__18_1-2_7_0/

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Valiron, G. [3] Lectures on the general theory of integral functions. Chel. Publ. Co. New York, (1949).