וְאִם֙ כָּל־בְּהֵמָ֣ה טְמֵאָ֔ה אֲ֠שֶׁר לֹא־יַקְרִ֧יבוּ מִמֶּ֛נָּה קָרְבָּ֖ן לַֽיהוָ֑ה וְהֶֽעֱמִ֥יד אֶת־הַבְּהֵמָ֖ה לִפְנֵ֥י הַכֹּהֵֽן׃
若是任何不潔淨的牲畜，就是人們不能從其中獻給永恆者作供物的，他要使那牲畜站在祭司面前。
Mishneh Torah, Positive Mitzvot
To carry out the ordinance of the Red Heifer so that its ashes shall be always available, as it is said, “And it shall be kept for the congregation….” (Num. 19:9).
Mishneh Torah, Positive Mitzvot
That one, who vows to the Lord the monetary value of an unclean beast, shall pay its value, as it is said, “…. then he shall set the beast (before the priest, and the priest shall value it)” (Lev. 27:11-13).
Sefer HaChinukh
The commandment of the appraisal of a beast, such that one give according to what the priest appraises: To rule in the case of appraisals of beasts according to that which the Torah commanded us about it — as it is stated (Leviticus 27:11-12), “and he shall place the beast in front of the priest. And the priest shall appraise it” — and to give according to the appraisal that the priest appraises, and not less. As a man should not decrease and lie about that which he opens his mouth for the Heavens; and it is even forbidden to lie with common things, as I explained above (Sefer HaChinukh 350).