RULE 16 & 23
 
16.Notice under Section6(6), &(3) and 8 :The notice under sub-section (6) of section 6, under sub-section (3) of section 7 or sub-section (1) or sub-section(3) of section 8, shall be issued by the assessing authority in Form VIII

Rule 23
23. Action for default by an enrolled person:If a person, liable to pay tax has wilfully failed to get himself enrolled, then without prejudice to the action that may be taken against him under sub-section (5) of section 6 the assessing authority shall after giving that person a reasonable opportunity ofbeing heard and after such inquiry, as may be deemed fit, or otherwise, assess the tax due to the best of its judgment and serve on him a notice of demand in Form XIV to pay the tax within fifteen days of receipt of the notice. Notice of hearing in such a case shall be issued by the assessing authority in Form XIII.The notice under sub-section (6) of Section 6 in respect of persons liable for enrolment shall also be in Form XIII.