This HTML5 document contains 5 embedded RDF statements represented using HTML+Microdata notation.

The embedded RDF content will be recognized by any processor of HTML5 Microdata.

PrefixNamespace IRI
isaphttp://webisa.webdatacommons.org/prov/
isahttp://webisa.webdatacommons.org/
rdfhttp://www.w3.org/1999/02/22-rdf-syntax-ns#
provhttp://www.w3.org/ns/prov#
xsdhhttp://www.w3.org/2001/XMLSchema#
n4freepatentsonline.
Subject Item
isa:314537100
rdf:type
prov:Entity
prov:value
In the past, different structural members were needed when using flexible cover made of material such as polyethylene or polyvinyl chloride on the one hand and relatively rigid covers made of such materials as fiberglass or aluminum on the other hand.
prov:wasQuotedFrom
n4:com
Subject Item
isap:62320232
prov:wasDerivedFrom
isa:314537100
Subject Item
isap:283181313
prov:wasDerivedFrom
isa:314537100