Blu Ray Extended Edition and Special DVD Extended Editition difference ?

Hello Gurus.
I just noticed that there was BR release of this trilogy and "Two Towers'" length is MORE than I've seen before - 235 min (Blu Ray Extended Edition) vs 223 min (Special DVD Extended Edition). Can someone explain, please, what is exact difference between these two versions ?
I don't mean count of DVDs or BR discs both versions have, I just want to know about movie length. Also, I'll be very glad if someone will explain DVD i BR versions length differences for "Fellowship of the ring" and "Return of the King" either.

Thanks in advance!
-t
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I found the answer from Wikipedia:
Film Theatrical edition Extended edition
The Fellowship of the Ring 178 mins 208 mins (228 with additional credits)
The Two Towers 179 mins 223 mins (235 with additional credits)
The Return of the King 200 mins 251 mins (263 with additional credits)

-- so those 8 minutes (235 mins in Two Towers at all) are about more credits at the end of this movie part. Thanks for watching :)