US2002164518-A1 -- US3720836-A   SIGRI ELEKTROGRAPHIT GMBH (SIGE);  US3996319-A   NUKEM GMBH (NUKE);  US4620839-A   KOBE SEIKO SHO KK (KOBM)   MORITOKI M,  MIKI H,  FUJIKAWA T,  MIYANAGA J,  KITAGAWA K;  US6974647-B2 -- DE4206490-A1   FRAUNHOFER GES FOERDERUNG (FRAU)   LEDJEFF K,  PEINECKE V;  EP174762-A   ENGELHARD CORP (ENGH)   KAUFMAN A,  WERTH J;  EP629015-A1   DE NORA PERMELEC SPA (ORON)   FAITA G,  MANTEGAZZA C;  EP690519-A1   JAPAN GORE TEX INC (NIGO)   KATO H,  TORIKAI E;  EP774794-A1   DAIMLER-BENZ AG (DAIM);  BALLARD POWER SYSTEMS INC (BLRD)   HARTMUT E;  JP01187349-A   ;  JP05101837-A   ;  JP07296818-A   ;  JP08124583-A   ;  JP08148170-A   ;  US3679485-A   ;  US3720836-A   SIGRI ELEKTROGRAPHIT GMBH (SIGE);  US3996319-A   NUKEM GMBH (NUKE);  US4219611-A   UNITED TECHNOLOGIES CORP (UNAC)   BREAULT R D;  US4555324-A   TOSHIBA KK (TOKE)   UENO M,  SHIROGAMI T,  MIKOGAMI Y;  US4620839-A   KOBE SEIKO SHO KK (KOBM)   MORITOKI M,  MIKI H,  FUJIKAWA T,  MIYANAGA J,  KITAGAWA K;  US4983472-A   INT FUEL CELLS CORP (ITFU)   KATZ M,  BONK S P,  MARICLE D L,  ABRAMS M;  US5176966-A   BALLARD POWER SYSTEMS INC (BLRD)   EPP D G,  WIENS B I;  US5187025-A   ANALYTIC POWER CORP (ANAL-Non-standard)   KELLAND J W,  BRAUN S G;  US5219674-A   INT FUEL CELLS CORP (ITFU)   SINGELYN J D,  ELMORE D E;  US5264299-A   INT FUEL CELLS CORP (ITFU)   KRASIJ M,  WATSON P R;  US5284718-A   BALLARD POWER SYSTEMS INC (BLRD)   RAMJI S,  WASHINGTON K B,  CHOW C Y,  WATKINS D S;  US5350643-A   HITACHI LTD (HITA)   IMAHASHI J,  HORIBA T,  MURANAKA T;  US5441621-A   UNITED TECHNOLOGIES CORP (UNAC)   MOLTER T,  FAYE D,  ARMSTRONG W;  US5480735-A   INT FUEL CELLS CORP (ITFU)   PLASSE P A,  LANDSMAN D A;  US5523175-A   INT FUEL CELLS INC (ITFU)   BEAL D,  MARTIN R G,  GORMAN M E;  US5565072-A   DE NORA PERMELEC SPA (ORON)   FAITA G,  MANTEGAZZA C;  US5837395-A   INT FUEL CELLS CORP (ITFU)   BREAULT R D,  FREDLEY R R,  SCHEFFLER G W;  US5976726-A   BALLARD POWER SYSTEMS INC (BLRD)   WILKINSON D P,  STUMPER J,  CAMPBELL S A,  DAVIS M T,  LAMONT G J;  US6165634-A   INT FUEL CELLS LLC (ITFU)   KRASIJ M,  MOSKEY E A;  US6261711-B1   PLUG POWER INC (PLUG-Non-standard)   MATLOCK R R,  BUESING D G;  US6338492-B1   FREUDENBERG FA CARL (FREU)   SCHILLING H,  HOFMANN G,  BOCK E;  US6350538-B1   BALLARD POWER SYSTEMS INC (BLRD)   WILKINSON D P,  CAMPBELL S A,  STUMPER J;  US6596427-B1   BALLARD POWER SYSTEMS INC (BLRD)   WOZNICZKA B,  DEVAAL J,  TABATABAIAN M;  WO1994009519-A1   ;  WO1995016287-A1   ;  WO1997008766-A2   ;  WO1997013287-A2