On the existence of an unambiguous solution in factor analysis of dynamic studies Samal, M. ; Karny, M. ; Surova, H. ; Penicka, P. ; Marikova, E. ; Dienstbier, Z. Abstract Publication: Physics in Medicine and Biology Pub Date: February 1989 DOI: 10.1088/0031-9155/34/2/006 Bibcode: 1989PMB....34..223S