D Alperovitch, P Greve, P Judge,
S Krasser… - US Patent …, 2011 - Google Patents
US PATENT DOCUMENTS 4,289.930 A 9/1981 Connolly et al. 4,384.325 A 5, 1983 Slechta
et al. 4,386,416 A 5, 1983 Giltner et al. 4,532.588 A 7, 1985 Foster 4,713,780 A 12/1987 …