Not much of Per Brinch Hansen’s programs/compilers/operating systems are available online, his books are the only source. Recently the sources of SuperPascal appeared online at his website (http://brinch-hansen.net/). This subset of Pascal, enhanced with constructs for parallel computing is not super Pascal, but a well structured, easy to understand compiler-interpreter combination for the study of concurrent programming.
Since the information is available in shar archive form, with Latex encoded documents. I took the liberty to convert the files to more convenient text and pdf format:
Sources of the compiler/interpreter. For Sun Pascal workstation, in nearly standard Pascal.
Note on the Sun Pascal clock statement used in the interpreter
See also the page on Superpascal
Solo Operating system, Concurrent Pascal, Sequential pascal
On bitsavers.org the Solo operating system disk is archived. Some kind person extracted the sources on the disk and made available the operating systeme Solo, Sequential Pascal and Concurrent Pascal compiler and the runtime sources for the PDP-11. Compared to SuperPascal, these are production quality products, well worth a study.