▁the ▁second ▁p ▁element ▁is ▁referring ▁to ▁a ▁book ▁by ▁ISBN ▁number . ▁ ▁The ▁resource ▁attribute ▁defines ▁a ▁resource ▁in ▁a ▁similar ▁way ▁to ▁the ▁href ▁attribute , ▁but ▁without ▁defining ▁a ▁hyper link . ▁ ▁Further ▁into ▁the ▁paragraph , ▁a ▁span ▁element ▁containing ▁an ▁about ▁attribute ▁defines ▁the ▁book ▁as ▁another ▁resource ▁to ▁specify ▁metadata ▁about . ▁ ▁The ▁book ▁title ▁and ▁author ▁are ▁defined ▁within ▁the ▁contents ▁of ▁this ▁tag ▁using ▁the ▁d c : title ▁and ▁d c : cre ator ▁properties . ▁ ▁Here ▁are ▁the ▁same ▁tri ples ▁when ▁the ▁above ▁document ▁is ▁automatically ▁converted ▁to ▁R DF / XML : ▁<? xml ▁version =" 1 . 0 " ▁encoding =" UTF - 8 "?> ▁< r df : R DF ▁xmlns : r df =" http :// www . w 3 . org / 1 9 9 9 / 0 2 / 2 2 - r df - syntax - ns # " ▁▁▁▁ ▁xmlns : fo af =" http :// xmlns . com / fo af / 0 . 1 /" ▁▁▁▁ ▁xmlns : dc =" http :// p url . org / dc / elements / 1 . 1 / "> ▁▁ ▁< r df : Description ▁r df : about =" http :// example . org / j ohn - d / "> ▁▁▁▁ ▁< dc : cre ator ▁xml : lang =" en "> J on athan ▁Do e </ dc : cre ator > ▁▁▁▁ ▁< fo af : primary