Question: When did Petah Tikva become the twinned administrative body of Gabrovo?
Paraphrase: on what date did Petah Tikva become the twinned administrative body of Gabrovo?
SPARQL (Wikidata): SELECT ?value WHERE { wd:Q190828 p:P190 ?s . ?s ps:P190 wd:Q180131 . ?s pq:P580 ?value}