As everyone noted above. However - the GURPS books are full of a LOT of useful and fun information. And some of the systems could be used in any Traveller game. The Far Trader book, which is based on a high-traffic, big ship universe, has some really interesting trade rules that have voumes of cargo between systems (I tend to divide by 100 to make it work for MTU).
As remarked elsewhere, the GURPS books are also well-researched so a useful source of information. And a lot of gaming stuff, even if couched in a specific rule set, can be used anywhere.
I've got maybe a half dozen physical Traveller GURPS books and use them as resources. Or just to look through as they are nice books.