## Innovations in Incidence Geometry

### An alternative existence proof of the geometry of Ivanov-Shpectorov for O'Nan's sporadic group

#### Abstract

We provide an existence proof of the Ivanov–Shpectorov rank $5$ diagram geometry together with its boolean lattice of parabolic subgroups and establish the structure of hyperlines.

#### Article information

Source
Innov. Incidence Geom., Volume 15, Number 1 (2017), 73-121.

Dates
Accepted: 16 December 2016
First available in Project Euclid: 28 February 2019

https://projecteuclid.org/euclid.iig/1551323010

Digital Object Identifier
doi:10.2140/iig.2017.15.73

Mathematical Reviews number (MathSciNet)
MR3713357

Zentralblatt MATH identifier
1385.51005

#### Citation

Buekenhout, Francis; Connor, Thomas. An alternative existence proof of the geometry of Ivanov-Shpectorov for O'Nan's sporadic group. Innov. Incidence Geom. 15 (2017), no. 1, 73--121. doi:10.2140/iig.2017.15.73. https://projecteuclid.org/euclid.iig/1551323010

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