I've read on O'Reilly's History of Programming Languages that Perl derives from nawk and sh.

I know that this may sound a little too simple, but I'd like to check if this information is accurate, since I'd like to include this in a course material I'm producing.

Nah, it's not that simple! There are plenty of descriptions of the various languages that influenced the design of Perl in the many books about the latter...

However one nice thing about Perl is its nice and thorough documentation. And to excerpt from perldoc perl:

Perl combines (in the author's opinion, anyway) some of the best fea-
tures of C, sed, awk, and sh, so people familiar with those languages
should have little difficulty with it.  (Language historians will also
note some vestiges of csh, Pascal, and even BASIC-PLUS.)  Expression
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