Yahya related to me from Malik from Nafi that on a journeyAbdullah ibn Umar did no more than the iqama, except for subh, when hecalled both the adhan and the iqama. Abdullah ibn Umar used to say,"The adhan is for an imam whom people join ."
App reference: Book 3, Hadith 12
USC-MSA web (English) reference: Book 3, Hadith 12
Arabic reference: Book 3, Hadith 158