PageHeader : Funkcialaj Ekvacioj, 30 (1987) 45-55 Title : Necessary and Sufficient Conditions of the Stability for Title : a Class of Second Order Nonlinear Oscillations AuthorInfo : By AuthorInfo : Zhongchao LIANG AuthorInfo : (Shandong College of Oceanography, The People's Republic of China) section : 1. Introduction section : 2. Lemmas section : 3. Boundedness and stability section : 4. Asymptotic stability section : References