Some excellent reminisces about the Vikings operated by BKS can be found in Arthur Whitlock's book 'Behind the Cockpit Door'. I got it from Transair a few years back but it seems to have disappeared from their catalog since then. Excellent book if you can find it, also includes quite a few stories on DC-3s, Ambassadors, Britannias and Tridents.
I recently did some research on three Vikings which have been used as a restaurant in Holland, the results of which can be found here:
http://www.vc10.net/History/vikings_of_soesterberg.html