Question: What is the official website of the feature film whose distributor is United Artists and whose publication date is 1971-12-15?
Choices: http://www.ci.scottsdale.az.us/
http://www.sofia.bg/en/index_en.asp
http://www.regina.ca/
http://www.mic.gov.to/
http://www.nyu.edu
http://lucasfilm.com/indiana-jones-and-the-raiders-of-the-lost-ark
http://www.konami.co.jp
https://www.daybreakgames.com/
http://www.co.marin.ca.us
http://www.svenskfilmdatabas.se/sv/item/?type=film&itemid=13936#release-dates
SPARQL: SELECT DISTINCT ?qpv WHERE { ?e <pred:instance_of> ?c . ?c <pred:name> "feature film" . ?e <distributor> ?e_1 . ?e_1 <pred:name> "United Artists" .  ?e <publication_date> ?pv . ?pv <pred:date> "1971-12-15"^^xsd:date . [ <pred:fact_h> ?e ; <pred:fact_r> <publication_date> ; <pred:fact_t> ?pv ] <official_website> ?qpv .  }
Program:
function: Find
inputs: United Artists
function: Relate
dependencies: 0
inputs: distributor
backward
function: FilterConcept
dependencies: 1
inputs: feature film
function: QueryAttrQualifier
dependencies: 2
inputs: publication date
1971-12-15
official website
Answer: http://www.svenskfilmdatabas.se/sv/item/?type=film&itemid=13936#release-dates