Yosef Karo, Translation:Shulchan Aruch — Orach Chaim 23Laws of tzitzit in cemeteries
“ Paragraph 3 — The laws of one who goes within four amot [1] of a corpse or of a grave are the same as those for one who enters a cemetery. In those places where it is the custom to remove the tzitzit from a dead person's tallit in the home, if the pallbearers wear tzitzit there is reason to suspect transgression of "mocking the poor." ”
