Muwatta 180

A ruling of Malik in the chapter on the call to prayer: he was asked about repeating the call and the iqama, and when people must stand when the prayer is called. He said he had not heard about the call and iqama beyond what people have done, and that the iqama is not repeated, which is what the scholars of Medina have always held. He had not heard a fixed limit for when people must stand when the prayer is called, and he thinks it depends on people's capacity, since some are heavy and some are light, and they cannot be like one man. The editor notes that Abu Mus'ab transmitted it from Malik, and that the Prophet ﷺ ordered Bilal to repeat the call in pairs and the iqama singly, as in Anas's report in the Sahihayn. ^{1 2}

Belongs to the Muwatta, Book of Prayer. Source: the Muwatta. Mentions Malik ibn Anas and Medina. Built on in the chapters on prayer.