Hadith 10:865
Abu Bakr narrated to us, he said: Hafs narrated to us, from Abd al-Malik, from Ata, who said: If he swears [to abstain from his wife] for less than four [months], then it is not *ila* (a vow of abstinence).
حدثنا أبو بكر قال نا حفص عن عبد الملك عن عطاء قال إذا حلف على دون الأربعة فليس بإيلاء