$ wget https://github.com/annosaxfdm/ontology/releases/latest/download/anno.ttl
...
$ rapper -i turtle -c anno.ttl
rapper: Parsing URI file:///home/konrad/projekte/rust/rickview/anno.ttl with parser turtle
rapper: Error - URI file:///home/konrad/projekte/rust/rickview/anno.ttl:17407 - syntax error, unexpected ., expecting a or URI literal or QName
rapper: Failed to parse file anno.ttl turtle content
rapper: Parsing returned 22890 triples

ontology$ scripts/combine
rapper: Parsing URI file:///home/konrad/projekte/anno/ontology/annodc.owl with parser rdfxml
rapper: Serializing with serializer ntriples
rapper: Parsing returned 267 triples
rapper: Parsing URI file:///home/konrad/projekte/anno/ontology/annods.owl with parser rdfxml
rapper: Serializing with serializer ntriples
rapper: Parsing returned 29667 triples
rapper: Parsing URI file:///tmp/anno.ttl with parser turtle
rapper: Serializing with serializer turtle
rapper: Parsing returned 29934 triples
ontology$ rapper -i turtle -c dist/anno.ttl
rapper: Parsing URI file:///home/konrad/projekte/anno/ontology/dist/anno.ttl with parser turtle
rapper: Error - URI file:///home/konrad/projekte/anno/ontology/dist/anno.ttl:17407 - syntax error, unexpected ., expecting a or URI literal or QName
rapper: Failed to parse file dist/anno.ttl turtle content
rapper: Parsing returned 22890 triples

#!/bin/sh
# Combine annodc.owl and annods.owl and convert it to anno.ttl.
SCRIPT_PATH=`dirname "$0"`
ROOT=`( cd "$SCRIPT_PATH/.." && pwd )`
DIST=$ROOT/dist
mkdir -p $ROOT/dist
rapper -i rdfxml $ROOT/annodc.owl -o ntriples > /tmp/annodc.nt
rapper -i rdfxml $ROOT/annods.owl -o ntriples > /tmp/annods.nt
# workaround for spaces in URIs
cat $SCRIPT_PATH/prefix.ttl /tmp/annodc.nt /tmp/annods.nt \
| sed  "s/\\\u0020/%20/g" \
> /tmp/anno.ttl
# resulting file is valid turtle but does not use prefixes yet
# reconvert to apply prefixes
rapper -i turtle -o turtle /tmp/anno.ttl > $DIST/anno.ttl