Some recent contributions have studied equilibrium ex ante investments by buyers and sellers, followed by matching and bargaining over the match surplus, with diverse findings. This paper sets up a simple model with both matching frictions and costs of switching bargaining partners, which encompasses existing contributions. We show that when switching costs are zero, in the limit as matching fr...

We present in this paper the first near infrared study of the young open cluster NGC 2244, which is well known for its partially embedded nature in the Rosette Nebula. Based on the spatially complete 2 Micron All Sky Survey, the young OB cluster indicates apparent substructures. It is surprisingly resolved into a compact core that matches well the congregation of massive OB stars in the optical...

We discuss the nature of some galactic open clusters by using proper motions and parallaxes from the Hipparcos and ACT catalogues. We show that the clusters Collinder 399, Upgren 1, NGC 1252 and Melotte 227 do not exist. Collinder 132 is found to be mainly composed out of members of an OB association, but there may be a star cluster present in this area too. Röser & Bastian (1994) proposed that...

References ml#ref-list-1 http://rspb.royalsocietypublishing.org/content/early/2010/10/15/rspb.2010.1864.full.ht This article cites 10 articles, 5 of which can be accessed free P<P Published online 20 October 2010 in advance of the print journal. Subject collections (2102 articles) evolution • (283 articles) taxonomy and systematics • Articles on similar topics can be found in the following co...

References #ref-list-1 http://rsbl.royalsocietypublishing.org/content/early/2012/05/14/rsbl.2012.0331.full.html This article cites 26 articles, 15 of which can be accessed free P<P Published online 16 May 2012 in advance of the print journal. Subject collections (61 articles) taxonomy and systematics • (526 articles) evolution • Articles on similar topics can be found in the following collect...