Some issue with references and rails

[kwerle]

[5] pry(#)> Mass.references some_object
ArgumentError: wrong number of arguments (1 for 0)
from /Users/kwerle/.rvm/gems/ruby-2.0.0-p0/gems/activesupport-3.2.13/lib/active_support/option_merger.rb:22:in `instance_variables'