Superpositions of time evolutions of a quantum system and a quantum time-translation machine
Yakir Aharonov, Jeeva Anandan, Sandu Popescu, and Lev Vaidman
Phys. Rev. Lett. 64, 2965 (1990) - Published 18 June, 1990
Soliton solutions to the gauged nonlinear Schrödinger equation on the plane
R. Jackiw and So-Young Pi
Phys. Rev. Lett. 64, 2969 (1990) - Published 18 June, 1990