Andy J. Wellings Bob Johnson Bo Sanden Jörg Kienzle Thomas Wolf Stephen Michell Object-Oriented Programming and Protected Objects in Ada 95. 16-28 2000 conf/adaEurope/2000 Ada-Europe db/conf/adaEurope/adaEurope2000.html#WellingsJSKWM00 http://dx.doi.org/10.1007/10722060_5