GB2330900-A -- GB2309072-A   ELCOR CORP (ELCO-Non-standard)   CAMPBELL R E,  WILKINSON J D,  HUDSON H M;  US5953935-A -- CA1048397-A   ORTLOFF CORP (ORTL-Non-standard)   CAMPBELL R E,  WILKINSON J D;  CA1073804-A   ORTLOFF CORP (ORTL-Non-standard)   CAMPBELL R E,  WILKINSON J D;  US4157904-A   ORTLOFF CORP (ORTL-Non-standard)   CAMPBELL R E,  WILKINSON J D;  US4278457-A   ORTLOFF CORP (ORTL-Non-standard)   CAMPBELL R E,  WILKINSON J D;  US4453958-A   GULSBY ENGG INC (GULS-Non-standard)   GULSBY J G,  COOK G D;  US4519824-A   RANDALL CORP (RAND-Non-standard)   HUEBEL R R;  US4617039-A   ORTLOFF CORP (ORTL-Non-standard);  PRO-QUIP CORP (PROQ-Non-standard);  ELCOR CORP (ELCO-Non-standard)   BUCK L L;  US4680042-A   EL PASO HYDROCARBONS (ELPA);  ADV EXTRACTION TECH (ADEX-Non-standard)   MEHRA Y R;  US4687499-A   MCDERMOTT INT INC (MCDE-Non-standard)   AGHILI H K;  US4695303-A   ;  US4696688-A   EL PASO HYDROCARBONS (ELPA);  ADV EXTRACTION TECH (ADEX-Non-standard)   MEHRA Y R;  US4698081-A   MCDERMOTT INT INC (MCDE-Non-standard)   AGHILI H K;  US4832718-A   ;  US4851020-A   MCDERMOTT INT INC (MCDE-Non-standard)   MONTGOMERY G J;  US4854955-A   ELCOR CORP (ELCO-Non-standard)   CAMPBELL R E,  WILKINSON J D,  HUDSON H M;  US4869740-A   ELCOR CORP (ELCO-Non-standard)   CAMPBELL R E,  WILKINSON J D,  HUDSON H M;  US4883515-A   ;  US4889545-A   ELCOR CORP (ELCO-Non-standard)   CAMPBELL R E,  WILKINSON J D,  HUDSON H M;  US5275005-A   ELCOR CORP (ELCO-Non-standard)   HUDSON H M,  CAMPBELL R E,  WILKINSON J D;  US5325673-A   KELLOGG CO M W (PULL)   PETTERSON W C,  DURR C A,  COYLE D A;  US5566554-A   KTI FISH INC (KTIF-Non-standard)   OSTASZEWSKI R J,  VIJAYARAGHAVAN B;  US5685170-A   MCDERMOTT ENGINEERS & CONSTRUCTORS LTD (MCDE-Non-standard)   SORENSEN J N;  US5890377-A   ABB RANDALL CORP (ALLM)   FOGLIETTA J H;  US5890378-A   ELCOR CORP (ELCO-Non-standard)   PIERCE M C,  HUDSON H M,  RAMBO C L,  WILKINSON J D;  GB2330900-B -- GB2309072-A   ELCOR CORP (ELCO-Non-standard)   CAMPBELL R E,  WILKINSON J D,  HUDSON H M