1. Ali ibn Muhammad has narrated from Muhammad ibn Ahmad from Muhammad ibn ‘Isa from certain persons of his people who has said the following: “This is concerning my question before abu al-Hassan , about the people who work for hire and we make a deal with them to farm for us and they say, ‘We have estimated this farm for so and so much and if you give it to us we guarantee your share according to our estimation.’ He (the Imam) asked, ‘Is it completed?’ I replied, ‘Yes, it is complete.’ He (the Imam) said, ‘It is not unlawful.’ I then asked, ‘He afterward comes and says that estimation is not as it was supposed to be and it is less.’ He (the Imam) said, ‘Do they return to you if it is more than estimated?’ I replied, ‘No, they do not return to us anything.’ He (the Imam) said, ‘You have the right to take according to the estimation, just as when it is more than estimation, they keep the extra, so also it is on them if it is less than estimation.’”