A maximum principle for nonlinear differential inequalities. - Chung-Fen Lee; Cheh-Chih Yeh (Appl. Math. Lett., 2003)

Lyapunov and Wirtinger inequalities. - Chung-Fen Lee; Cheh-Chih Yeh; Chen-Huang Hong; Ravi P. Agarwal (Appl. Math. Lett., 2004)

An oscillation theorem. - Chung-Fen Lee; Cheh-Chih Yeh (Appl. Math. Lett., 2007)