I got the terms from _Software Requirements and Specifications_, which is a fun, if fluffy and meandering, read. I only skimmed the paper you linked but it seem

I got the terms from _Software Requirements and Specifications_, which is a fun, if fluffy and meandering, read. I only skimmed the paper you linked but it seems to be a more thorough treatment than the book was. https://www.amazon.com/Software-Requirements-Specifications-Principles-Prejudices/dp/0201877120 https://www.amazon.com/Software-Requirements-Specifications-...