[1] Hayman W. Meromorphic Function. Oxford: Clarendon Press, 1964

[2] Yang Lo. Value Distribution Theory and New Research. Beijing: Science Press, 1982(in Chinese)

[3] Yi Hongxun, Yang Chungchun. The Uniqueness Theory of Meromorphic Functions. Beijing: Science
Press, 1995 (in Chinese)

[4] Hille E. Ordinary Differential Equations in the Complex Domain. New York: Wiley, 1976

[5] Frei M. Uber die subnormalen losungen der differentialgleichung w′′ + e−zw′ + (konst.)w = 0. Comment
Math Helv, 1962, 36: 1-8

[6] Ozawa M. On a solution of w′′ + e−zw′ + (az + b)w = 0. Kodai Math J, 1980, 3: 295-309

[7] Gundersen G. On the question of whether f′′ + e−zf′ + B(z)f = 0 can admit a solution f 6≡ 0 of finite
order. Proc R S E, 1986, 102A: 9-17

[8] Langley J K. On complex oscillation and a problem of Ozawa. Kodai Math J, 1986, 9: 430-439

[9] Amemiya I, Ozawa M. Non-existence of finite order solutions of w′′ +e−zw′ +Q(z)w = 0. Hokkaido Math
J, 1981, 10: 1-17

[10] Chen Zongxuan. The growth of solutions of the differential equation f′′ + e−zf′ + Q(z)f = 0. Science in
China (Series A), 2001, 31: 775-784 (in Chinese)

[11] Li Chunhong, Huang Xiaojun. The growth of solution of a class of high order differential equations (in
chinese). Acta Mathematica Scientia, 2003, 23A(6)

[12] Gundersen G. Estimates for the logarithmic derivative of a meromorphic function, plus similar estimates.
J London Math Soc, 1988, 37(2): 88-104

[13] Gundersen G. Finite order solutions of second order linear differential equations. Trans Amer Math Soc,
1988, 305: 415-429

[14] Markushevich A I. Theory of Functions of a Complex Variable, Vol.2. Translated by Silverman R A. N J
Prentice-Hall: Englewood Cliffs, 1965

[15] He Yuzan, Xiao Xiuzhi. Algebroid Functions and Ordinary Differential Equations. Beijing: Science Press,
1988(in Chinese)

[16] Valiron G. Lectures on the General Theory of Integral Functions. New York: Chelsea, 1949