Mishneh Torah — Positive Mitzvot מצוות עשה, Chapter 168
The full Hebrew text of Mishneh Torah, Positive Mitzvot, Chapter 168, with English translation by Maimonides (Rambam).
לישב בסוכה שבעת ימים, שנאמר: "בסוכות תשבו, שבעת ימים" (ויקרא כג,מב).
To dwell in a sukkah for seven days, as [Leviticus 23:42] states: "And you shall dwell in sukkot for seven days."