Niklaus Wirth is a gifted writer. His easy to read style and the simplicity that must have taken so much effort to achieve makes his books jewels in the often so obscure computer science world.

A list of his publications is at his homepage. The books listed below are the full books in PDF format

	Pascal User_Manual and Report Second Edition
	Pascal User_Manual and Report Fourth Edition ISO standard
	Algorithms+ Data Structures = Programs, 1976
	Algorithms+ Data Structures = Programs, 1976, Chapter 5: PL/0 Compiler
	Algorithms+ Data Structures = Programs, 2004, Oberon version
	Algorithms+ Data Structures = Programs, 2012, Oberon version
	Algorithms+ Data Structures = Programs, 2017, Oberon version
	Compiler Bau, 1986, German
	Compiler Bouw 1986, Dutch
	Compiler construction 1996
	Compiler Construction, 2005 (PDF), (TXT)
	CompilerConstruction 2014 part 1, part 2
	CompilerConstruction 2017 part 1, part 2
	Modula-2 Handbook
	Programming in Oberon 1992
	Programming in Oberon, 2004
	Programming in Oberon, 2015
	Project Oberon, 2005
	Project Oberon, Chapter 1-9, 2013 Project Oberon, Chapter 10-15, 2013 Project Oberon, Chapter 16, 2013 RISC Architecture, 2014 RISC5 Architecture Update, 2018 How to use the Oberon System, 2015
	The School of Niklaus Wirth

Besides these books scanned in PDF format, the next books are also on my shelf: