The S-LINK Interface Specification
http://www.cern.ch/HSI/s-link/
If you have a hard-copy of this Specification, please check that the date on the front-page (top-left corner) matches the one in the WWW version.
If you are browsing this Specification on WWW and want a hard-copy you can either preview the PostScript Version and print it out using your local PostScript Viewer or you can use anonymous FTP to the machine www.cern.ch and then get the file:
/pub/hsi/s-link/s-link.ps