Table schema:
CREATE TABLE table_name_86 (entrant VARCHAR, driver VARCHAR, chassis VARCHAR, constructor VARCHAR, tyre VARCHAR)

Question: Can you say what was the entrant of maserati built item with a Tyre of p with a chassis of 250f a6gcm that was driven by Luigi Villoresi?
SQL: SELECT entrant FROM table_name_86 WHERE constructor = "maserati" AND tyre = "p" AND chassis = "250f a6gcm" AND driver = "luigi villoresi"