The first should be: In the meeting, we discussed three topics, the details of which are shown below.
The second is also correct.
This is the usage note from American Heritage Dictionary:
The American Heritage® Dictionary of the English Language, Fourth Edition copyright ©2000 by Houghton Mifflin Company. Updated in 2009. Published by Houghton Mifflin Company. All rights reserved.
Usage Note: It has sometimes been claimed that whose is properly used only as the possessive form of who and thus should be restricted to animate antecedents,
as in a man whose power has greatly eroded. But there is extensive literary precedent for the use of whose with inanimate antecedents, as in The play, whose style
is rigidly formal, is typical of the period. In an earlier survey this example was acceptable to a large majority of the Usage Panel. Those who avoid this usage employ
of which: The play, the style of which isrigidly formal, is typical of the period. But as this example demonstrates, substituting of which may producea stilted sentence
. See Usage Notes at else, which, who.
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