Discussions in this thread have mentioned Niklaus Wirth's Pascal and
later languages. In my big handbook on mathematical function
computation,

    https://doi.org/10.1007/978-3-319-64110-2

about a large library for binary and decimal floating-point arithmetic
written in C, I included appendices about interfacing that library to
other important programming languages: Ada, C#, C++, Fortran, Java,
and Pascal.

Since the book appeared, I've written freely distributable virtual
book appendices for COBOL, Go, Modula-2, Oberon, and Rust. The two
for Modula-2 and Oberon are available as PDF files at this small site:

    http://www.math.utah.edu/~beebe/modula-2/

They each discuss multiple compilers, and the serious problem of lack
of module compatibility across compilers, which addresses a question
mentioned on this list.

The works of Niklaus Wirth are covered here:

    https://www.math.utah.edu/pub/bibnet/authors/w/wirth-niklaus.bib
    https://www.math.utah.edu/pub/bibnet/authors/w/wirth-niklaus.html

With all of our bibliography archives at Utah, the two look similar on
the screen, but the first is for BibTeX, and the second has live
hyperlinks for Web browsers.

This is likely the most extensive bibliography about Wirth anywhere on
the Internet, and after months of searching following his death on New
Year's Day this year, I have failed to turn up anything more.

Finally, there is active development of the GNU Modula-2 compiler,
gm2, with list archives at

    https://lists.nongnu.org/archive/html/gm2

Some Linux O/S distributions now have binary packages for gm2, and
some of us on that list hope that Modula-2 support will soon be much
more widely available than it has been for the last couple of decades.

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