Sahih Muslim Book 10, Hadith Number 3906.

Chapter : How much land is to be spared when there is disagreement over the breadth of path.

Ibn ‘Abbas (Allah be pleased with them) reported that when Allah’s Prophet (may peace be upon him) came to Medina, they were paying one and two years in advance for fruits, so he said: Those who pay in advance for anything must do so for a specified weight and for a definite time.