jetssky has a website
http://www.jetssky.com you can buy their flights, but when you proceed through the booking, I noted
operated by Hola Airways a Spanish Charter, as far as I can make out
they do offer flights on their website from Maastricht Aachen Aiport to
Athens | Barcelona | Las Palmas | Malaga | Malmö | Nice | Oslo | Rome | Stockholm
all start in Jan 2004 or later