Inventor
FIELDHOUSE DOUGLAS M
US4 patents
Patents
4 patentsUS7242922B2Jul 10, 2007
Toll free calling account recharge system and method
VESTA CORP20 citations87
US6404866B1Jun 11, 2002
Telephone calling account system and method
VESTA CORP48 citations85
US7979051B2Jul 12, 2011
Toll free calling account recharge system and method
VESTA CORP1 citations57
US7539480B2May 26, 2009
Toll-free calling account recharge system and method
VESTA CORP2 citations57