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http://www.amazon.com/Relativity-Its-Roots-Banesh-Hoffmann/dp/0486406768
"Relativity and Its Roots" by Banesh Hoffmann, Chapter 5.
(I do not have the text in English so I am giving it in French)
Banesh Hoffmann, "La relativite, histoire d'une grande idee", Pour la
Science, Paris, 1999, p. 126:
"Dans un cas, je compare votre horloge a deux des miennes; dans
l'autre, vous comparez la mienne a deux des votres; ceci permet a
chacun de nous d'observer, sans absurdite, que l'horloge de l'autre
est plus lente que la sienne."

Translation from French: "In one case, I compare your clock with two
of mine; in the other case, you compare my clock with two of yours:
this allows each of us to observe, without absurdity, that the clock
of the other is slower than his own."

The following observer has two clocks placed on the periphery of a
rotating disc, and is going to compare them with a single non-rotating
clock (at rest):

http://www.bartleby.com/173/23.html
Albert Einstein (1879-1955).  Relativity: The Special and General
Theory.  1920.
XXIII.  Behaviour of Clocks and Measuring Rods on a Rotating Body of
Reference
"An observer who is sitting eccentrically on the disc K' is sensible
of a force which acts outwards in a radial direction..."

The only difficulty comes from the fact that the two rotating clocks
are not inertial. However, by increasing the diameter of the disc
while keeping the linear speed of the periphery constant, one can make
them virtually inertial.

Pentcho Valev
pvalev@yahoo.com