[1] V. Beneš: 
Extremal and optimal solutions in the transshipment problem. Comment. Math. Univ. Carolinae 33 (1992), 97-112. 
MR 1173751 
[2] R. G. Douglas: 
On extremal measures and subspace density. Michigan  Math. J. 11 (1964), 243-245. 
MR 0185427 | 
Zbl 0121.33102 
[3] N. Dunford, J. T. Schwartz: 
Linear Operators. Part I: General Theory. Interscience Publishers, New York 1963. 
MR 1009162 
[4] R. H. Farell: 
Representation of invariant measures. Illinois J. Math. 6 (1962), 447-467. 
MR 0150264 
[5] J.H.B. Kemperman: 
On the role of duality in the theory of moments. In: Proc. Semi-Infinite Programming and Applications 1981 (Lecture Notes in Economics and Math. Systems 215), Springer-Verlag, Berlin - Heidelberg - New York 1983, pp. 63-92. 
MR 0709269 
[6] D. Linhartova: 
Extremal solutions of a general marginal problems. Comment. Math. Univ. Carolinae 32 (1991), 743-748. 
MR 1159821 
[8] J. Štěpán: 
Simplicial measures and sets of uniqueness in marginal problem. Statistics and Decisions (to appear). 
MR 1257863 
[9] H. von Weizsacker, G. Winkler: 
Integral representation in the set of solutions of a generalized moment problem. Math. Ann. 246 (1979), 23-32. 
MR 0554129