http://schema.rdfs.org/all.ttl isn't valid

[timrdf]

http://schema.rdfs.org/all.ttl

schema:accessibilityAPI a rdf:Property;
    rdfs:label "Accessibility API"@en;
    rdfs:comment "Indicates that the resource is compatible with the referenced accessibility API (WebSchemas wiki lists possible values).
     "@en;
    rdfs:domain schema:CreativeWork;
    rdfs:range xsd:string;
    rdfs:isDefinedBy <http://schema.org/CreativeWork>;

bash-3.2$ rapper -v
2.0.9

bash-3.2$ rapper -g -c all.ttl 
rapper: Parsing URI file:///all.ttl with parser guess
rapper: Guessed parser name 'turtle'
rapper: Error - URI file:///all.ttl:4029 - syntax error at '"'
rapper: Failed to parse file all.ttl guess content
rapper: Parsing returned 3372 triples