Siman 80, Some of the Melachos that are Assur on Shabbos, Paragraph 87-end of the Siman and Siman 81, The Four Domains With Regard to Shabbos, Paragraphs 1-2.
Siman 80, Some of the Melachos that are Assur on Shabbos, Paragraph 87-end of the Siman and Siman 81, The Four Domains With Regard to Shabbos, Paragraphs 1-2.