Yoreh Deah Siman 21 Seif 2

ב אִם שָׁחַט בִּבְהֵמָה הָאֶחָד כֻּלּוֹ וַחֲצִי הַשֵּׁנִי, וּבְעוֹף שְׁנֵי חֲצָאֵי סִימָנִים, פְּסוּלָה.

Seif 2

 

If one slaughters with one animal one full sign and half of a second one, and with a fowl you slaughtered both signs both half of each it is not acceptable.