وقال أبو يوسف ومحمد لا يحتاج إلى تسمية رأس المال إذا كان معينا
Translation: Abu Yusuf and Muhammad say that when the capital is individually designated, a separate naming of its amount is not necessary.
Abu Yusuf and Muhammad differ where the advance payment is a specifically identified countervalue. They consider that clear identification can, in that situation, replace an additional statement of its quantity; Abu Hanifa still insists on specification of the amount.
This is not a disagreement over whether the price must be paid in full during the session. The advance-payment requirement remains; the difference concerns how the amount of already-identified capital must be established.