中国科学院数学与系统科学研究院期刊网
Notes on Levin Type Inequalities of Harmonic Functions
Guo Chang WU, Yu Dong REN, Bai Yun SU
Acta Mathematica Sinica, Chinese Series . 2015, (3): 431 -434 .  DOI: 10.12386/A2015sxxb0043