مُسْنَدُ أَحْمَدَ
Musnad Ahmad 3070
Musnad of 'Abdullah bin al-'Abbas bin 'Abdul-Muttalib from the Prophet
It was narrated from Ibn ‘Abbas (رضي الله عنه) that He disliked unripe dates (busr) to be soaked on their own and he said: The Messenger of Aliah (ﷺ) forbade muzza' (nabeedh made in green glazed pitchers or varnished jars) and he disliked unripe dates (busr) to be soaked on their own.
Musnad Ahmad 3095Its is isnad is saheeh]