On the Solvability of Nonlinear Third-Order Two-Point Boundary Value Problems. - Ravi P. Agarwal; Petio S. Kelevedjiev; Todor Z. Todorov (Axioms, 2020)

Existence for Two-Point nth Order Boundary Value Problems under Barrier Strips. - Ravi P. Agarwal; Todor Z. Todorov; Petio S. Kelevedjiev (Symmetry, 2023)