PDF: https://susam.github.io/tucl/the-unix-command-language.pdf
HTML: https://susam.github.io/tucl/the-unix-command-language.html
The PDF document is a scanned copy of the first ever paper that was published on the Unix shell. The paper was written by Ken Thompson and published in Structured Programming (Infotech state of the art report).
The scanned copy was first obtained from Ken Thompson by wesleyneo and shared on archive.org. I combined the scanned images into a single PDF document and shared it here. Also, wesleyneo transcribed the paper to text format and I further edited and reformatted it to Markdown format. The HTML document is automatically generated from the Markdown file.
All of these files are shared on the Internet with permission from Ken Thompson.