A degree theory for compact perturbations of proper<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" alttext="$C^{1}$"><mml:msup><mml:mi>C</mml:mi><mml:mn>1</mml:mn></mml:msup></mml:math>Fredholm mappings of index<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" alttext=" $0$"><mml:mn>0</mml:mn></mml:math>
Abstract and applied analysis