LC has used BM695.P35 for works on "Sale of hametz" (sh 91004452).
The BT for "Sale of hametz" is "Hametz," and the BT for "Hametz" (sh 91004447) is
"Passover--Customs and practices" (sh 85098535).
"Passover--Customs and practices" has the 053  BM695.P35.
LC would  tend to use BM695.P3 for more general works.

Lenore Bell