- References
- External links
In algebraic topology, a branch of mathematics, a quasi-fibration, introduced by Albrecht Dold and René Thom, is a continuous map of topological spaces 
such that the fibers 
are homotopy equivalent to the homotopy fiber of f via the canonical map.
Every fibration is a quasi-fibration, but the converse is not true. For instance, the projection of the letter L to its base interval is a quasi-fibration (all fibers are contractible), but not a fibration.
References
- {{Citation | last1=Dold | first1=Albrecht | last2=Thom | first2=René | authorlink1= Albrecht Dold | authorlink2= René Thom | title=Quasifaserungen und unendliche symmetrische Produkte | jstor=1970005 | mr=0097062 | year=1958 | journal=Annals of Mathematics |series=Second Series | issn=0003-486X | volume=67 | pages=239–281 | doi=10.2307/1970005}}
- {{Citation|last=May|first=J.Peter|authorlink=J. Peter May|
contribution=Weak equivalences and quasifibrations|title= Groups of self-equivalences and related topics (Montreal, PQ, 1988)|pages= 91–101|
series=Lecture Notes in Mathematics|volume= 1425|publisher= Springer|location=Berlin|year= 1990|mr=1070579|chapter-url=http://www.math.uchicago.edu/~may/PAPERS/67.pdf|doi=10.1007/BFb0083834}}
External links
- http://mathoverflow.net/questions/53782/quasifibrations-and-homotopy-pullbacks
- http://mathoverflow.net/questions/60763/when-a-quasifibration-is-a-hurewicz-fibration
- http://www.lehigh.edu/~dmd1/tg516.txt
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