About: http://webisa.webdatacommons.org/243083902

Property	Value
http://www.w3.org/1999/02/22-rdf-syntax-ns#type	http://www.w3.org/ns/prov#Entity
http://www.w3.org/ns/prov#value	Another form is a pad or mat of the type shown in U.S. Pat. No. 4,417,568 (Nozawa et al., Nov. 29, 1983), which has the advantage of being foldable but the disadvantage of being hard and, therefore, uncomfortable.
http://www.w3.org/ns/prov#wasQuotedFrom	freepatentsonline.com