Sahih Bukhari Volume 3, Book 34, Hadith Number 353.

Narated By ‘Abdullah bin ‘Umar : Allah’s Apostle forbade the sale called ‘Habal-al-Habala which was a kind of sale practiced in the Pre-lslamic Period of ignorance. One would pay the price of a she-camel which was not born yet would be born by the immediate offspring of an extant she-camel.