Bottesini's Tre Gran Duetti for Two DBs

[Illfavor]

Does anyone have the Yorke edition of this? Is it to be performed an octave higher than it is written? There is a download of this available online (not sure if it's legal, so I didn't keep it) but it was edited by Rodney Slatford (who I know does Yorke editing) and it appeared as though it should have been played an octave higher.

Are there any other available editions of this?

[Mr.Phil]

I bought some edition of this from lemur and it was meant to be played an octave higher.