Abu al-Khasib (may Allah have mercy on him) says that Suwayd bin Ghafalah (may Allah have mercy on him) used to lead us in prayer in Ramadan, and he would lead twenty rak'ahs in five sets (that is, four rak'ahs at a time).
(b) Shutayr bin Shakal (may Allah have mercy on him), who was one of the companions of Sayyiduna Ali (may Allah be pleased with him), when he led them in prayer in Ramadan, would pray twenty rak'ahs of tarawih and three rak'ahs of witr.
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الصلاة / 4619