Mention the years in which 'Logic Programming: Further Developments' and 'Ein Virtueller Dokumentenserver f\u00FCr Digitale Bibliotheken' were published.
When were the publications 'Logic Programming: Further Developments' and 'Ein Virtueller Dokumentenserver f\u00FCr Digitale Bibliotheken' published?
SELECT DISTINCT ?answer WHERE { { <https://dblp.org/rec/conf/slp/Gallaire85> <https://dblp.org/rdf/schema#yearOfPublication> ?answer } UNION { <https://dblp.org/rec/conf/btw/Zeitz01> <https://dblp.org/rdf/schema#yearOfPublication> ?answer } }
<https://dblp.org/rec/conf/slp/Gallaire85> <https://dblp.org/rec/conf/btw/Zeitz01>