Classification (of information) 2 3D-consistency 1 3d-consistency 1 Backlund transformations 1 Bäcklund transformations 1 CD4+ T-cells 1 Consistency property 1 Continuous functions 1 Darboux transformations 1 Difference equations 1 HIV infection 1 Integrable lattice equation 1 Integrable lattice equations 1 Lattice equation 1 Mathematical transformations 1 Nonlinear equations 1 Partial difference equations 1 Quad-graph 1 Quad-graph equation 1 Quad-graph equations 1 Soliton solutions 1 Solitons 1 Zero-sets 1 continuous Galerkin-Petrov method 1 non-linear supply rate Mathematics Subject Classification: 34A12, 34K28 1