question: Did M1 and M2 marry a founder of M0
query: SELECT count(*) WHERE {
  ?x0 ns:organization.organization_founder.organizations_founded M0 .
  FILTER ( M1 != ?x0 ) .
  FILTER ( M2 != ?x0 ) .
  M1 ns:people.person.spouse_s/ns:people.marriage.spouse|ns:fictional_universe.fictional_character.married_to/ns:fictional_universe.marriage_of_fictional_characters.spouses ?x0 .
  M2 ns:people.person.spouse_s/ns:people.marriage.spouse|ns:fictional_universe.fictional_character.married_to/ns:fictional_universe.marriage_of_fictional_characters.spouses ?x0
  }