the skylab missions was part of what mission?
Entity Entity Entity Entity
m.01zrms m.034s5v m.02qdb3 m.0j5r5v7
Skylab 2 Skylab 4 Skylab 3 Skylab 1
class entity
spaceflight.space_mission m.0hmw487
spaceflight.space_mission spaceflight.space_program
Space Mission Skylab Missions
none none
spaceflight.space_mission.space_program
Space program
PREFIX rdf: <http://www.w3.org/1999/02/22-rdf-syntax-ns#> PREFIX rdfs: <http://www.w3.org/2000/01/rdf-schema#> PREFIX : <http://rdf.freebase.com/ns/> 
SELECT (?x0 AS ?value) WHERE {
SELECT DISTINCT ?x0  WHERE { 
?x0 :type.object.type :spaceflight.space_mission . 
VALUES ?x1 { :m.0hmw487 } 
?x0 :spaceflight.space_mission.space_program ?x1 . 
FILTER ( ?x0 != ?x1  )
}
}
(AND spaceflight.space_mission (JOIN spaceflight.space_mission.space_program m.0hmw487))