This is from combined archives that french and canadian collections put online. There is a deficient english version of the database search. Of course the documents are all french, and there are many pertaining to Detroit and Cadillac. A lot of legal battles between Cadillac and the company chartered by the king to exploit fur trading in that part of New France. Some of the links do not work. You can check by clicking the head icon below the text icon at left of a description. You can also enter Cadillac or other Michigan sites in the search box at top of page.
There are legal documents, certificates that serve in payment for services rendered. There is a
9-page document describing all of Cadillac's belongings at Detroit. There are minutes of proceedings [[council) between Ottawa, huron and miami chiefs and Cadillac.

This one is a description of Detroit by Cadillac himself in 1701. His introduction goes like this:

The job of a warrior not being equal to that of a writer, it is not without temerity I must attempt describe a country much more deserving of a better pen than mine. But since you ordered a description, I shall endeavour to do so by saying...

my translation.

here is the link to the archives;

http://bd.archivescanadafrance.org/s...x=0&y=0#resume