Y Zhang, SA Meyer, A McCabe, JE Stahmann… - US Patent …, 2011 - Google Patents
3,920,005 A 11/1975 Gombrich et al. 4,388,927 A 6, 1983 Schober 4.550, 221 A 10, 1985
Mabusth 4,562,841 A 1/1986 Brockway et al. 4,562,842 A 1, 1986 Morfeld et al. 4,686,332 A …