530 ADDITIONAL PHYSICAL FORM AVAILABLE NOTE (R)Indicators - Both undefined; each contains a blank (^)Subfield Codes $a Additional physical form available note (NR) $b Availability source (NR) $c Availability conditions (NR) $d Order number (NR) $u Uniform Resource Identifier (R) $z Source of note information (NR) (AM CF VM SE) [OBSOLETE] $3 Materials specified (NR) $6 Linkage (NR) $8 Field link and sequence number (R)