21. The expert from IMMA introduced ECE/TRANS/WP.29/GRRF/2017/14 as amended GRRF-84-13 with provisions allowing additional conditions for the activation of the stop lamp. The expert from Canada recommended addressing this question within GTR No. 3. The Chair noted that ETRTO would not be allowed to propose amendments to GTR No. 3 and asked whether a Contracting Party to the 1998 Agreement could sponsor this amendment. GRRF raised the question why the author of the proposal selected provisions from Regulation No. 13 and not from Regulation No. 13-H. The expert from IMMA agreed to submit a revised proposal for the February 2018 session of GRRF.