app/presenters/hyku/manifest_enabled_work_show_presenter.rb
# unlike doi, there can be multiple isbns
unlike doi, there can be multiple isbns
unlike doi there can be multiple isbns
def isbns
      isbn_regex = /((?:ISBN[- ]*13|ISBN[- ]*10|)\s*97[89][ -]*\d{1,5}[ -]*\d{1,7}[ -]*\d{1,6}[ -]*\d)|
                    ((?:[0-9][-]*){9}[ -]*[xX])|(^(?:[0-9][-]*){10}$)/x
      isbns = extract_from_identifier(isbn_regex)
      isbns.flatten.compact if isbns
    end
def isbns isbn_regex = / ((?:ISBN[- ]*13|ISBN[- ]*10|) \s *97[89][ -]* \d {1,5}[ -]* \d {1,7}[ -]* \d {1,6}[ -]* \d )|
                    ((?:[0-9][-]*){9}[ -]*[xX])|(^(?:[0-9][-]*){10}$) /x isbns = extract_from_identifier ( isbn_regex ) isbns . flatten . compact if isbns end
unlike doi, there can be multiple isbns
unlike doi there can be multiple isbns