Mixed feelings. You should get credit because it is your work. Whichever individual took the info and made the .pdf probably did take credit for it and at the very least that is plagiarism. Depending on how the law is written, possibly theft.

OTOH, once you put the info out on the internet, you are sort of telling folks, "here is a list of things I've compiled and it's now in the public domain". Theft might be a hard sell, plagiarism is clear cut.

My opinion, not knowing much about copyright legalities.