You're not supposed to view them in your web
browser.
It should work fine that way, assuming the pdf plugin is sending the
right html commands to the web server. I see people reading docs this
way all the time.
To answer the original question, the WCS card is documented in the
1000 M/E/F Engineering Reference
http://www.bitsavers.org/pdf/hp/1000/1000_MEF_EngrRef/
92851-90001_Mar81_6.pdf section B