Reference for Genesis 42:8

וַיַּכֵּ֥ר יוֹסֵ֖ף אֶת־אֶחָ֑יו וְהֵ֖ם לֹ֥א הִכִּרֻֽהוּ׃

And Joseph knew his brethren, but they knew him not.

BDB