Mishnah Meilah 4:4: Piggul and notar do not combine because they have two different names. Creeping animal and animals which died without being properly slaughtered and similarly animals which died without being properly slaughtered and the meat of a dead animal do not combine to transmit impurity, even in the more lenient [feature] of the two. Food that have become impure through [by coming in contact with] an av hatumah [Primary source of impurity which renders even vessels and persons impure, all the more so foodstuffs] or that have become impure through [by coming in contact with] a velad hatumah [something rendered impure on a derivative level, by contact ultimately with an original source of impurity] can combine with each other to transmit impurity as the more lenient of the two.

הפיגול והנותר אין מצטרפין זה עם זה. מפני שהם שני שמות. השרץ והנבלה. וכן הנבלה ובשר המת. אין מצטרפין זה עם זה. לטמא אפילו כקל שבשניהם. האוכל שנטמא באב הטומאה ושנטמא בולד הטומאה. מצטרפין זה עם זה. לטמא כקל שבשניהם:

Mishnah Meilah 4:5: All foods combine to invalidate a body, [if one consumed] in the amount similar to a half of a loaf of bread; [so too] the amount of food needed for two meals for an eruv [a halachic merging of separate domains by means of setting aside an amount of food in a designated place]; [so to] the size of an egg in order to transmit food impurity [to other things]; the size of a dry fig to make one liable for carrying out on Shabbat; the size of a [large] date to make one liable on [for eating on] Yom Kippur. All liquids combine to invalidate the body with a revi'it [specific unit of volume]; and the "cheek-full" size to make one liable on Yom Kippur.

כל האוכלין מצטרפין לפסול את הגויה בכחצי פרס. במזון שתי סעודות לערוב. בכביצה לטמא טומאת אוכלין. בכגרוגרת להוצאת שבת. בככותבת ביום הכפורים. כל המשקין מצטרפין לפסול את הגויה. ברביעית. ובמלא לוגמיו ביום הכפורים: