Regarding the "development and history of foil kites", Wikipedia says:
"One of the first available 4-line kites was the Quadrifoil, designed by Ted Dougherty, popular as a buggy kite in the mid-1990s. The Quadrifoil in its original design became known as the 'Classic' - the kite was rectangular in shape in contrast to today's more elliptical designs. Later evolutions of the kite were sold as the Competition (more elliptical in design - C1, C3), Q2000 range, and lastly the Competition X range (XXS, XS, XM, XL and the XXL). Although these were sold under the Quadrifoil brand-name by Active People, none of these were designed by Dougherty himself."
You might check with the good folks on this forum:
http://www.powerkiteforum.com/viewthread.php?tid=22123