tag:digital.library.illinois.edu,2005:/items/4e1ba850-73cd-0134-1deb-0050569601ca-7Mechanical Perspective: Backing2023-07-20T13:43:09Ztag:digital.library.illinois.edu,2005:Item/590392016-11-01T16:04:05Z2023-07-20T13:43:09ZMechanical Perspective: BackingUniversity of Illinois at Urbana-Champaign Library