2139.9 is the gauge for what locomotive class?
Entity Entity Entity
m.0g0d12 m.0fyjkb m.0g155m
South Devon Railway Remus class South Devon Railway Eagle class South Devon Railway Dido class
class literal
rail.locomotive_class 2139.9^^http://www.w3.org/2001/XMLSchema#float
rail.locomotive_class type.float
Locomotive class 2139.9
none none
rail.locomotive_class.gauge_mm
Gauge (mm)
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 :rail.locomotive_class . 
VALUES ?x1 { "2139.9"^^<http://www.w3.org/2001/XMLSchema#float> } 
?x0 :rail.locomotive_class.gauge_mm ?x1 . 
FILTER ( ?x0 != ?x1  )
}
}
(AND rail.locomotive_class (JOIN rail.locomotive_class.gauge_mm 2139.9^^http://www.w3.org/2001/XMLSchema#float))