I have ported an old GFA book to HYPertext. It's attached to this post. You will need an ST-Guide or equivalent HYPertext reader.
If you also want the disk that came with the book, it's here:https://www.dev-docs.org/docs/
PS. I know the book is old and maybe some of the example code is not so great, but hey, it's free.
Released with kind permission of Clayton Walnum, aka Taylor Ridge Books.
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