I’m writing a book/play/screenplay, and I want to quote the lyrics of an Armstrong song. May I do so?

The Louis Armstrong House Museum cannot grant permission for these types of projects, as it does not hold the copyrights to any lyrics. Unless your use qualifies as “fair use” under the Copyright Act of 1976, you must find out who the copyright holder is for the lyrics of the particular song you’re interested in, and contact that individual or organization. Often, but not always, the rights are held by the publisher that issued the song, but there may be other rights holders as well.