ABSTRACT
Remark. Since {supp gil is locally finite then every point XES has a neighborhood intersecting only one finite number of supp gi. Therefore the previous sum is well defined because it can hold only a finite number ofterms for each x. I
D A partition of unity {gil is subordinate to an open covering {L'i} of S if for every gi there is at least an open lJj such that supp gi c lJj . In other words: if {supp gi} is a refinement of {L'i}.
