Columbia subject headings:
Differential equations, Nonlinear.
Solitons.
Spectral theory (Mathematics)
Transformations (Mathematics)
Harvard subject headings:
Differential equations, Nonlinear.
Solitons.
Spectral theory (Mathematics)
Transformations (Mathematics)
Princeton subject headings:
Differential equations, Nonlinear.
Solitons.
Spectral theory (Mathematics)
Transformations (Mathematics)