US 6341717, Auer, Günter, "Metering pump dispenser with at least two metering pumps", published 2002-01-29, assigned to Megaplast GmBH
US 5740947, Flaig, Raymond Michael; Turbett, James Lynn & Bertolini, Peter, "Dual compartment pump dispenser", published 1998-04-21, assigned to Chesebrough-Pond's USA Co.
US 5875936, Turbett, James Lynn & Iaia, Mark John, "Refillable pump dispenser and refill cartridge", published 1999-03-02, assigned to Chesebrough-Pond's USA Co.
EP 0048420, Wiegner, Georg & Geneschen, Peter, "Dispenser", published 1984-02-15, assigned to Henkel KGaA