مُسْنَدُ أَحْمَدَ
Musnad Ahmad 3367
Musnad of 'Abdullah bin al-'Abbas bin 'Abdul-Muttalib from the Prophet
It was narrated that an old man of Banu Sadoos said: Ibn ‘Abbas (رضي الله عنه) was asked about kissing for one who is fasting. He said: The Messenger of Allah (ﷺ) used to kiss his wives' heads when he was fasting.
Musnad Ahmad 3391Saheeh; this is a da'eef isnad]