Aarna, Agu Chemical engineering in the Estonian S.S.R. / by Agu Aarna ; [translated from Estonian by Ilmar Koppel]. - Perioodika, 1978. - 62, [1] p., [16] leaves of plates : ill. ; 20 cm. ISBN: 0.35rub (pbk.) LCCN: 80514846 Nat. Bib. No.: USSR*** Subjects--Topical Terms: Chemical engineering--History.--Estonia Subjects--Index Terms: ქიმიური ტექნოლოგიები ქიმიური მრეწველობა LC Class. No.: TP86.E75 / A213 Dewey Class. No.: 338.4/766/0094741 Universal Decimal Class. No.: 66