An article here about the open-sourcing of Comal, nearly 20 years ago. But also a bit of a love letter to a structured language which is simple and small and familiar to Basic users:
Comal has been set free by Jos Visser
Here’s the home page of the OpenComal project.
There’s a bit of an update in this thread on stardot.
Acorn offered a version of COMAL on ROM for the BBC Micro - the 450 page manual has been remastered here.
The included SSD disc image contains some of the longer listings and examples from the book, along with a copy of the COMAL ROM. Boot the disc with Shift+Break to get an index of the programs and which page of the book they relate to.