/**
  * @see Filter::getSupportedTransformation()
  */
 function getSupportedTransformation()
 {
     // We transform all types of OpenURL schema to NLM citation
     return parent::getSupportedTransformation('lib.pkp.classes.metadata.openurl.OpenUrlBaseSchema', 'lib.pkp.classes.metadata.nlm.NlmCitationSchema');
 }
 /**
  * Constructor
  */
 function OpenUrlNlmCitationSchemaCrosswalkFilter()
 {
     // We transform all types of OpenURL schema to NLM citation
     parent::OpenUrlCrosswalkFilter('OpenUrlBaseSchema', 'NlmCitationSchema');
 }
 /**
  * Constructor
  */
 function NlmCitationSchemaOpenUrlCrosswalkFilter()
 {
     // We transform NLM citation to all types of OpenURL schema
     parent::OpenUrlCrosswalkFilter('NlmCitationSchema', 'OpenUrlBaseSchema');
 }