Section 3(2)(a) in Central Excise (Appeals) Rules, 2001
(a)in the case of an individual, by the individual himself or where the individual is absent from India, by the individual concerned or by any person duly authorised by him in this behalf; and where the individual is a minor or is mentally incapacitated from attending to his affairs, by his guardian or by any other person competent to act on his behalf;