diff --git a/app/models/journal_paper.rb b/app/models/journal_paper.rb
index fbc1265..3630718 100644
--- a/app/models/journal_paper.rb
+++ b/app/models/journal_paper.rb
@@ -58,7 +58,7 @@ class JournalPaper
     title << self.journal_title if self.journal_title.present?
     title << self.vol_no if (self.vol_no.present? && self.vol_no != "0")
     title << self.issue_no if (self.issue_no.present? && self.issue_no != "0")
-    title << "pp"+self.form_to_start+"-"+self.form_to_end if (self.form_to_start.present? && self.form_to_start != "0")
+    title << "pp"+self.form_to_start.to_s+"-"+self.form_to_end.to_s if (self.form_to_start.present? && self.form_to_start != "0")
     title << ( !self.journal_levels.blank? ? "(#{self.journal_levels.collect{|x| x.title}.join(', ')})" : nil)
     # if !self.publication_date.nil?
     #   pd = self.publication_date.strftime("%Y-%m-%d").split('-')