diff	2008-10-14 14:47:54 - revision [ Version = 4 --> (current) ] by bci1 physical perturbation' or `signal'

diff	2008-10-14 14:47:01 - revision [ Version = 3 --> Version 4 ] by bci1

diff	2008-10-14 14:45:37 - revision [ Version = 2 --> Version 3 ] by bci1 (see also \PMlinkname{Hamiltonian operator}{QuantumHamiltonianOperator})

diff	2008-10-14 14:30:45 - revision [ Version = 1 --> Version 2 ] by bci1 types of wave equations