Sunan an Nasai
1498
Sahih+2

It was narrated that Asma' bint Abi Bakr said:The Messenger of Allah (ﷺ) prayed during an eclipse. He stood for a long time, then he bowed for a long time, then he stood up and (remained standing) for a long time, then he bowed for a long time, then he stood up, then he prostrated for a long time, then he stood up and (remained standing) for a long time, then he bowed for a long time, then he stood up, then he prostrated for a long time, then he sat up, then he prostrated for a long time, then he sat up and then he finished

SahihAbu Ghuddah
SahihAl-Albani