http://www.mindspring.com/~loop_antenna/amloop_calc4.htm

http://www4.tpgi.com.au/users/ldbutler/Loop18MHz.htm

http://www.mindspring.com/~loop_antenna/

http://www.hard-core-dx.com/nordicdx/antenna/loop/hulaloop.html

http://home.datacomm.ch/hb9abx/loop1-e.htm

http://www.frontiernet.net/~jadale/Loop.htm

http://entropy.brneurosci.org/loopantenna.html

http://www.io.com/~n5fc/loop_ant.html

http://www.schmarder.com/radios/misc-stuff/loops.htm

http://www.wellbrook.uk.com/

http://beradio.com/notebook/radio_shieldedloop_am_antenna_2/

http://www.wellbrook.uk.com/antennashop/index.php?route=product/product&product_id=33