Tossefta sur Le Lévitique 15:1

One who sees one issue of zov (i.e., an unnatural flow or discharge, discussed in Lev. 15:1-15)): Beit Shammai say that he is like [a menstruant] who observes a day for a day^*i.e., a clean day for each day she experiences a discharge (see Niddah 4:7). And Beit Hillel say that he is like a ba'al keri (i.e., one experiences a seminal discharge). Both sides concede that he may immerse and eat his Pesach offering in the evening. Beit Hillel said to Beit Shammai, "Do you not concede that he may immerse and eat his Pesach offering in the evening [like a ba'al keri]? Beit Shammai said to them, "Do you not concede that if he sees [an issue of zov] the next day, that he is impure?" Behold, he is therefore like [a menstruant] who observes a day for a day, who would be [deemed] impure if she saw [blood] the next day." One who moves [the discharge] seen [by the zav]: Beit Shammai say, [his purity status] is contingent, [and] Beit Hillel say, he is pure. His beddings and his seats: Beit Shammai say, [their purity status] is contingent, and Beit Hillel say, they are pure. [If] he saw two issues, the one who moved both of them is impure, according to the words of Beit Shammai. And Beit Hillel say, the one who moved the first one is pure, and the second one is impure. His beddings and his seats: Whether [he sat or lay on them prior to] the first or the second sighting, Beit Shammai render them impure, and Beit Hillel render them pure. [If] one sighting is of as great a quantity as two [normal sightings], the one who moved all of it is impure, the words of Beit Shammai, and Beit Hillel says, only the one who moved the last drop is impure. Said Rabbi Akiva, Beit Shammai and Beit Hillel did not disagree about one who [on the first day] saw two, or one that was of as great a quantity as two, and then it stopped on the second day (i.e., he had no sighting of zov), and on the third day he saw one, [for both agree] that he is a full-fledged zav. About what did they disagree? About one who sees one [issue of zov] on the first day, and on the second day it stopped, and on the third day he saw two [issues of zov], [as to which] Beit Shammai say that he is a full-fledged zav, and Beit Hillel render his bedding and seating impure, and he requires immersion in living waters, and he is exempt from [bringing] an offering.