In Birds of East Africa by Stevenson and Fanshawe Hartlaub's Bustard is depicted with pale yellow iris.

Therefore at first when I saw Davids nice picture I was sure he had made a fault. However after searching the net I found no pictures of pale-eyed Hartlaub's.

So obviously a mistake in "Birds of East Africa"?

Best wishes, Rune

Yes, Rune, David shows a marked brown or reddish brown iris.

Praed & Grant, 1952, illustrate yellowish iris.
My 20 random picks on Google 'Hartlaub's B. photo' displayed yellowish iris, so Stevenson et al. are hardly absolutely wrong.
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Smile :
By the way, the German ornithologists Theodor von Heuglin, and Gustav Hartlaub exchanged surnames when coining scientific names of Hartlaub's and Heuglin's Bustard in 1863 and 1859, respectively.

Hartlaub also named a bird after himself (!), viz.
the Principe Sunbird, A. hartlaubii (1857).
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