- warn "Unsupported PublicationType: ".(ref($ref->{MedlineCitation}->{Article}->{PublicationTypeList}->{PublicationType})?
- join(',',@{$ref->{MedlineCitation}->{Article}->{PublicationTypeList}->{PublicationType}}):
- $ref->{MedlineCitation}->{Article}->{PublicationTypeList}->{PublicationType});