A hybrid variational method for beam propagation and interaction in a graded-index nonlinear waveguide. - Tran Ky Vi; Nguyen Dang Quang Huy; Tran Chi Quy; Bui Duc Tinh; Le Minh Thu; Doan Quang Tri; Marek Trippenbach; Nguyen Viet Hung (Commun. Nonlinear Sci. Numer. Simul., 2024)