Who founded M2 and M3 , founded a film producer , founded M4 , and was employed by M1
SELECT DISTINCT ?x0 WHERE {
?x0 a ns:people.person .
?x0 ns:organization.organization_founder.organizations_founded ?x1 .
?x0 ns:organization.organization_founder.organizations_founded M2 .
?x0 ns:organization.organization_founder.organizations_founded M3 .
?x0 ns:organization.organization_founder.organizations_founded M4 .
?x0 ns:people.person.employment_history/ns:business.employment_tenure.company M1 .
?x1 a ns:film.producer
}