IOD format

Curtis Haase (73007.2024@compuserve.com)
Mon, 24 May 1999 12:31:05 -0400

Where can I find a complete definition of the IOD format used to
report positional observations?  I couldn't seem to find this information
on the VSO web site.

Thanks,
Curtis Haase
73007.2024@compuserve.com