´Abu Hurairah said:` "The Messenger of Allah said: 'Dates for dates, wheat for wheat, barley for barley, salt for salt, exchanged hand to hand. Whoever gives more or takes more has engaged in Riba unless they are of different types."
Hadith Referenceسنن نسائي / كتاب البيوع / 4563
Hadith Gradingالألبانی:صحيح | زبیر علی زئی:صحيح مسلم