Mishneh Torah — Positive Mitzvot מצוות עשה, Chapter 227
The full Hebrew text of Mishneh Torah, Positive Mitzvot, Chapter 227, with English translation by Maimonides (Rambam).
להיות בית דין הורגין בחנק, שנאמר: "מות יומת הנואף, והנואפת" (ויקרא כ,י).
For a court to execute by strangulation, as [Leviticus 20:10] states: "The adulterer and the adulteress shall die."