projects active in calendar year 1972 Pennsylvania State University Center for Air Environment Studies. text ncu Research Triangle Park, N.C Environmental Protection Agency, Office of Air Quality Planning and Standards ; [for sale by the Supt. of Docs., U.S. Govt. Print. Off.] 1972 monographic eng iii, 385 p. 27 cm. Compiled by (the) Center for Air Environment Studies of the Pennsylvania State University. Contract no.168-02-0077. Air Pollution Research cno 920121 20160527184509.0 30347