Mistakenly put frozen heart before universal literary hero (6,2,7)

I believe the answer is:

rupert of hentzau

'literary hero' is the definition.
(I've seen this before)

'mistakenly put frozen heart before universal' is the wordplay.
'mistakenly' indicates an anagram.
'before' says to put letters next to each other.
'universal' becomes 'u'.
'put'+'frozen'+'heart'='putfrozenheart'
'putfrozenheart' with letters rearranged gives 'rupertofhentza'.
'rupertofhentza'+'u'='RUPERT OF HENTZAU'

(Another definition for rupert of hentzau that I've seen is " literary hero".)

I've seen this clue in The Telegraph.

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