Federal Trade Commission publications can easily be found online, and they are the law so are they usable?
Intellectual Property Law Attorney
While FTC publications may offer useful guidance in interpreting certain laws and regulations, they are not "the law." A court is not bound to follow the FTC. Rather, it is the FTC, as a government agency, that must abide by and follow the courts' decisions. That being said, an FTC publication may have persuasive effect (depending on the facts and circumstances of your case). However, the support for your legal analysis should not be limited to FTC publications.
You can cite to the FTC publication (the Blue Book citation format would include the url and the date it was accessed). It also would be advisable to submit a copy with a declaration authenticating where (url) and when (print date) it was accessed. This would make it easier for the court to consider the FTC publication (and it is to your benefit to make things easier rather than harder for the court to rule in your favor). Because the FTC is publicly available and it would be easy to independently confirm its contents, the court can take judicial notice of the fact that the FTC published the document (but the court is not bound by the statements or findings in the FTC publication), but this formality usually is unnecessary unless the opposing party wants to challenge its authenticity (and it often will not if it can confirm the publication is being accurately cited).
This answer is for informational purposes only. It is not intended as specific legal advice regarding your question. The answer could be different if all of the facts were known. This answer does not establish an attorney-client relationship.