Bharatiya Jyotihshastra (History of Indian Astronomy), translated by R. V. Vaidya v2.c13.s2.7

v2.c13.s2.7

The work *Ratnamālā* by Śrīpati treats in these very subjects and nothing else, which have been mentioned so far, as forming the contents of the Muhūrta works. Śrīpati has only not named this work as a muhūrta work. Later on people actually began to name such works as Muhūrta Mārtanda (movable), sthira (fixed) etc. given to signs, Mars and other lords of signs, Nanda and other names given to the tithis, lords of tithis and similar other things. For example the performance of a rite to ensure ‘fixity’ or stability under the influence of a ‘movable’ nakṣatra is regarded as inauspicious: if the birth nakṣatras of the bride and the bridegroom be Rohiṇī and Uttarāṣāḍhā respectively, then the union would prove unfortunate because these (nakṣatras) are regarded as coming under the categories of snake and mongoose who are natural enemies and so on.