Papers about Quad Band PIFA design

hello all,

I want to design Quad Band PIFA GSM850/900/1800/1900.
Can any body provide reference designs for this?I'm badly in need of this.........

Advance thanks.......

Try to read these three papers:

1. https://www.edaboard.com/viewtopic.php?p=459271#459271
2 & 3. posted here