+++ /dev/null
-class Citation < ActiveRecord::Base
- belongs_to :reference_of, :class_name => "Book", :foreign_key => :book2_id
-
- belongs_to :book1, :class_name => "Book", :foreign_key => :book1_id
- belongs_to :book2, :class_name => "Book", :foreign_key => :book2_id
-end