Natyashastra
परिवर्तनमेवं स्यात्तस्यान्ते प्रविशेत्ततः । चतुर्थकारः पुष्पाणि प्रगृह्य विधिपूर्वकम् ॥ ९९॥
The transition should be performed in this manner. At its conclusion, the performer should enter. The fourth participant, holding flowers, should proceed according to the prescribed ritual.
english translation
parivartanamevaM syAttasyAnte pravizettataH । caturthakAraH puSpANi pragRhya vidhipUrvakam ॥ 99॥
hk transliteration by Sanscript