app/views/customers/_segment.html.erb
<div class="segments">
<% new_or_existing = authorship.new_record? ? 'new' : 'existing' %>
<% prefix = "source[#{new_or_existing}_authorship_attributes][]" %>
<% fields_for prefix, custumer_segments do |custumer_segments_form| %>
<p>
<%= custumer_segments_form.collection_select(:segment_id, Author.find(:all), :id, :name, :include_blank => true)$
<%= link_to_function "remove", "$(this).up('.authorship').remove()" %>
</p>
<% end %>
</div>