When was the research paper on Delivery supply chain by University of Lisbon published?
University of Lisbon published a paper on Delivery supply chain in what year?
SELECT DISTINCT ?answer WHERE { <https://dblp.org/rec/conf/cec/FariaSSSK06> <https://dblp.org/rdf/schema#authoredBy> ?x . ?x <https://dblp.org/rdf/schema#primaryAffiliation> 'University of Lisbon, Portugal' . <https://dblp.org/rec/conf/cec/FariaSSSK06> <https://dblp.org/rdf/schema#yearOfPublication> ?answer }
<https://dblp.org/rec/conf/cec/FariaSSSK06>