And from him, from Muhammad ibn al-Husayn from Mu'awiyah ibn Hakim from Abu Malik al-Hadrami from Abu al-Jarud, who said:
I said to Abu Ja’far عليه السلام, peace be upon him: “At what distance is the shortening (of prayer)?” Imam عليه السلام said: “At a ‘barid’.”
Ali Akbar al-Ghaffari
Tahdhīb al-Aḥkām fī Sharḥ al-Muqniʿah, vol. 3, p. 229