27. GRB noted that, in line with the WP.29 decision, the secretariat was preparing a concept of a central register in which acronyms used by WP.29 as well as definitions used in UN Regulations and UN GTRs would be listed. In this context, GRB reiterated its request to OICA and IMMA to update documents GRB-57-12 and GRB-57-18 containing definitions and acronyms in Regulations under the responsibility of GRB.