# Felix Klein's paper on real flexes vindicated

Banach Center Publications (1998)

- Volume: 44, Issue: 1, page 195-210
- ISSN: 0137-6934

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topRonga, Felice. "Felix Klein's paper on real flexes vindicated." Banach Center Publications 44.1 (1998): 195-210. <http://eudml.org/doc/208883>.

@article{Ronga1998,

abstract = {In a paper written in 1876 [4], Felix Klein gave a formula relating the number of real flexes of a generic real plane projective curve to the number of real bitangents at non-real points and the degree, which shows in particular that the number of real flexes cannot exceed one third of the total number of flexes. We show that Klein's arguments can be made rigorous using a little of the theory of singularities of maps, justifying in particular his resort to explicit examples.},

author = {Ronga, Felice},

journal = {Banach Center Publications},

keywords = {enumerative problems; JFM 08.0439.01; number of real flexes; real plane projective curve},

language = {eng},

number = {1},

pages = {195-210},

title = {Felix Klein's paper on real flexes vindicated},

url = {http://eudml.org/doc/208883},

volume = {44},

year = {1998},

}

TY - JOUR

AU - Ronga, Felice

TI - Felix Klein's paper on real flexes vindicated

JO - Banach Center Publications

PY - 1998

VL - 44

IS - 1

SP - 195

EP - 210

AB - In a paper written in 1876 [4], Felix Klein gave a formula relating the number of real flexes of a generic real plane projective curve to the number of real bitangents at non-real points and the degree, which shows in particular that the number of real flexes cannot exceed one third of the total number of flexes. We show that Klein's arguments can be made rigorous using a little of the theory of singularities of maps, justifying in particular his resort to explicit examples.

LA - eng

KW - enumerative problems; JFM 08.0439.01; number of real flexes; real plane projective curve

UR - http://eudml.org/doc/208883

ER -

## References

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