Norm had posted info about this website potentially having malware spyware imbedded in files . I agree and would suggest you NOT download items . I apologize for posting this and perhaps remove it to avoid anyone getting a compromised computer system , PDF books usually are a safe file format but them bored tweaking programmers are stealthy buggers
There is a risk of malware no matter where we go. Like everything else, we need to exercise due caution. I get emails from scammers posing as Facebook, Costco, Home Depot, etc, etc. and others with all kinds of special offers and rewards. On an average day I get more items in my junk mail bucket than I do in worthwhile messages.
The only way to be 100% safe is stay off the internet entirely.
Having said that, keep the security software up to date, and when in doubt: DELETE!