- Sandhu, G. S.; Sonntag, D. Updates to MOVES Heavy Duty Running Exhaust Rates: Diesel, Gasoline, and Natural Gas. MOVES Review Work Group, Office of Transportation and Air Quality, U.S. Environmental Protection Agency, Ann Arbor, Michigan, April 2019. Link.
- Sandhu, G. S.; Sonntag, D. B.; Sanchez, J. Identifying Areas of High NOx Operation in Heavy-Duty Vehicles. 28th Annual Real World Emissions Workshop of the Coordinating Research Council, Garden Grove, California, March 2018. Link.
- Sandhu, G. S.; Sonntag, D. Recommended Updates to MY 2010+ Heavy-Duty Vehicles - Fixed Mass Factor and Diesel Particulate Matter Rates. MOVES Review Work Group, Office of Transportation and Air Quality, U.S. Environmental Protection Agency, Ann Arbor, Michigan, December 2017. Link.
- Sandhu, G. S.; Sonntag, D. B.; Sanchez, J. In-Use Emission Rates for MY 2010+ Heavy-Duty Diesel Vehicles. 27th Annual Real World Emissions Workshop of the Coordinating Research Council, Long Beach, California, March 2017. Link.
- Sandhu, G. S.; Sonntag, D. Update to Running Exhaust Criteria Pollutant Emission Rates for Model Year 2010+ Heavy-Duty Diesel Vehicles. MOVES Review Work Group, Office of Transportation and Air Quality, U.S. Environmental Protection Agency, Ann Arbor, Michigan, December 2016. Link.
- Sandhu, G. S.; Sonntag, D. B.; Hamady, F. Effect of Driving Conditions on NOx Emissions from 2010+ Heavy-Duty Vehicles. 26th Annual Real World Emissions Workshop of the Coordinating Research Council, Newport Beach, California, March 2016. Link.
- Ropkins, K.; Sandhu, G. S.; Burnette, A. D. 2015. A Novel Multiplexed Sensor-Based Approach to Mobile Particle Mass and Number Measurement. 25th Annual Real World Emissions Workshop of the Coordinating Research Council, Long Beach, California, March 2015.
- Sandhu, G. S.; Frey, H. C.; Bartelt-Hunt, S.; Jones, E. Real-World Activity and Fuel Use of Diesel and CNG Refuse Trucks. PEMS International Conference and Workshop, CE-CERT, University of California-Riverside, April 2014.
- Sandhu, G. S.; Frey, H. C. Energy Use and Emissions from Diesel and Biodiesel Blends for Earthmoving Equipment. 106th Annual Conference & Exhibition of the Air & Waste Management Association, Chicago, Illinois, June 2013.
- Frey, H.C.; Sandhu, G.S.; Sun, Y.; Lee, T.; Swidan, H.; Liu, B.; Babaee, S. Incorporating Vehicle Portable Emissions Measurement Systems into the Classroom. 104th Annual Conference & Exhibition of the Air & Waste Management Association, Orlando, Florida, June 2011.