Northern hydraulics sells a book that teaches building trailers

I found two Northern Hydraulics. *northernhydraulics.net in MT, and
northernhydraulics.com in Ireland. *I couldn't find any books on either
web site. *Did I miss something?

http://northerntool.com/
These guys keep changing their name. Their old name was "Northern
Hydraulics", which is what most of us still think of them as, but
mostly I think they just call themselves "Northern" now.
--Glenn Lyford