<http://webisa.webdatacommons.org/115972329> <http://www.w3.org/ns/prov#wasQuotedFrom> <issuu.com> . <http://webisa.webdatacommons.org/115972329> <http://www.w3.org/ns/prov#value> "Stemming is inert material such as gravel inserted into the collar of the drill hole to confine the explosive gases. 4." . <http://webisa.webdatacommons.org/115972329> <http://www.w3.org/1999/02/22-rdf-syntax-ns#type> <http://www.w3.org/ns/prov#Entity> . <http://webisa.webdatacommons.org/prov/103495445> <http://www.w3.org/ns/prov#wasDerivedFrom> <http://webisa.webdatacommons.org/115972329> .