1) WWI grp 2) Army under Pershing 3) Average emission factor 4) Doughboys of WWI 5) Initials from 1917 6) Initials of 1917 7) Men of 1917 8) Us army in europe 9) WWI gr 10) Wwi group 11) WWI military gp 12) Wwi military group 13) WWI troop gp 14) WWI troop group 15) WWI troops 16) WWI US group 17) Yanks of WWI 
acronym: Average emission factor
Allied Expeditionary Force