What is the abbreviation for Proceedings the international symposium plasma chemistry?

Looking for the shorthand of Proceedings the international symposium plasma chemistry or how to abbreviate it? We have 2 shorthands for Proceedings the international symposium plasma chemistry.

PROC INT SYMP PLASMA CHEM — Proceedings of the International Symposium on Plasma Chemistry
PROC ISPC — Proceedings of the International Symposium on Plasma Chemistry