הלכה על כתובות 111:16

From the laws of this commandment - that which our Rabbis, may their memory be blessed, said (Ketuvot 56a) what is the law of one who stipulates [to marry] his wife "on condition that you do not have [the rights] from me of flesh, covering and time period"; that which they said (Ketuvot 61a), "A woman rises with [the economic standards of a new] husband, but does not descend," and hence we calculate her food and clothing [allowance] according to his elevation; the matter of the differentiation of time periods, which is according to the strain of the man's profession, to the point where they, may their memory be blessed, said (Ketuvot 62b) that the time period of a sailor is twice a year, a camel rider once a month and a Torah scholar once a week and it is fitting for him that it be on Shabbat night; and the rest of its details - are [all] elucidated scattered in the Order of Nashim.