Nearly-quaternionic Kähler manifolds of dimension at least $8$ are shown to be quaternionic Kähler. Restrictions on the covariant derivative of the fundamental four-form of a semi-quaternionic Kähler are also found.
@article{107623,
author = {Andrew Swann},
title = {Some remarks on quaternion-Hermitian manifolds},
journal = {Archivum Mathematicum},
volume = {033},
year = {1997},
pages = {349-354},
zbl = {0910.53023},
mrnumber = {1601349},
language = {en},
url = {http://dml.mathdoc.fr/item/107623}
}
Swann, Andrew. Some remarks on quaternion-Hermitian manifolds. Archivum Mathematicum, Tome 033 (1997) pp. 349-354. http://gdmltest.u-ga.fr/item/107623/
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