Genchev Y, Lulchev T, Hristodorova D. INFLUENCE OF THE TYPE OF UPHOLSTERY MATERIALS ON THE SOFTNESS OF UPHOLSTERY WITH INNER SPRING UNITS. INNO [Internet]. 2016 May 19 [cited 2026 Apr. 14];5(1). Available from: http://innojs.ltu.bg/index.php/scjournal-inno/article/view/203