| GRPE-66-42 | Progress report of the REC informal group to the GRPE | |
| GRPE/2013/6 | Proposal for a new regulation on Retrofit Emissions Control (REC) Devices | |
| GRPE-66-28 | Proposal to amend the draft proposal for a new UN Regulation on REC | |
| GRPE-66-06 | Flow charts for the draft REC regulation-version 00 | |
| GRPE-66-07 | Proposal for an amendment to the new UN Regulation concerning REC devices for heavy duty vehicles | |
| GRPE-66-08 | Memo of the REC informal group chair concerning NO2 requirement for class 2 REC |