Encased innerspring mattress and cover device is assembled by positioning mattress and cover component layers, one atop the other, in sequential order, (namely mattress cover bottom, bottom panel, filling material, insulator, innerspring, insulator, filling material, top panel, and mattress cover top,...http://www.google.com.au/patents/US5065485?utm_source=gb-gplus-sharePatent US5065485 - Enclosed innerspring mattress cover and process for assembling same
