The relevant provisions of subsection 4(1) are:
Eligible person means a person who —
(a)is an Australian soldier;
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and includes a widow, widower or dependent parent of a person specified in any of the paragraphs (a) to (g) of this definition;
Australian Soldier ... includes
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(h)a national serviceman;
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National serviceman means a person who is a national serviceman in accordance with section 4AAB;
Section 4AAB Subject to this section, a person is a national serviceman for the purposes of this Act if —
(a)he was, immediately before 7 December 1972, a national serviceman, or a national service officer, for the purposes of the National Service Act 1951-1971 serving in the Regular Army Supplement; and
(b)on or after that date —
(i)he completed the period of service in that Force for which he was to be deemed to have been engaged to serve or for which he was appointed, as the case may be, or
(ii)that service ended by reason of his death or his discharge, or the termination of his appointment, on the ground of invalidity or physical or mental incapacity to perform duties.