The following links are a good starting place for Bluetooth trace antennas
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Research Articles
 - http://www.ece.uic.edu/pdfs/wlan.pdf
 - http://ieeexplore.ieee.org/xpl/abs_free.jsp?arNumber=1268485

Centurion Article
 - http://www.centurion.com/home/pdf/WCDMA_2.pdf