The rules that use the category "<digit-not_zero-sing>" are:

<contact_type-simple>

<digit-not_zero-sing> <contact_type_nom-sing>

<minute_duration-sing>

<digit-not_zero-sing>

<up_to_two_digits-sing>

<digit-not_zero-sing>

<tens_number-sing>

<digit-not_zero-sing>

<contact_type-sing-neutral>

<digit-not_zero-sing> <contact_type_nom-sing-neutral>

<contact_type-point_id_type_none-simple>

<digit-not_zero-sing> <contact_type_nom-point_id_type_none-sing>

<time_interval>

<digit-not_zero-sing> <time_interval_unit-hour-sing> and <minute_duration-pl> <time_interval_unit-minute-pl>

<digit-not_zero-sing> <time_interval_unit-hour-sing> and <minute_duration-sing> <time_interval_unit-minute-sing>

<tens_number-not_digit_sequence-sing>

<digit-not_zero-sing>

<contact_type-point_id_type_none-sing-simple-neutral>

<digit-not_zero-sing> <contact_type_nom-point_id_type_none-sing-neutral>

<contact_type>

<digit-not_zero-sing> <contact_type_nom-point_id_type_none-sing>

<digit-not_zero-sing> <contact_type_nom-sing>

<contact_type-point_id_type_none>

<digit-not_zero-sing> <contact_type_nom-point_id_type_none-sing>

<contact_type-point_id_type_none-sing-neutral>

<digit-not_zero-sing> <contact_type_nom-point_id_type_none-sing-neutral>