The rules that use the category "<contact_attribute>" are:

<contact_command_mod>

<contact_attribute>

<controller_flight_advisory>

<contact_type-pl-neutral> <confirmation_relation-pl> <contact_attribute>

<contact_type-sing-neutral> <confirmation_relation-sing> <contact_attribute>

<controller_flight_advisory-not_recursive-adj>

<contact_type-pl-neutral> <confirmation_relation-pl> <contact_attribute>

<contact_type-sing-neutral> <confirmation_relation-sing> <contact_attribute>