Ibrahim bin Nafi' (may Allah have mercy on him) said that al-Hasan bin Muslim (may Allah have mercy on him) used to pray between Maghrib and Isha, and he said that al-Hasan (may Allah have mercy on him) mentioned that Tawus (may Allah have mercy on him) did not regard it as anything (significant).
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الصلاة / 4753