duplicated.bib~

% @article{thune2009variation,
%  title={Variation theory applied to students’ conceptions of computer programming},
%  author={Thun{\'e}, Michael and Eckerdal, Anna},
%  journal={European Journal of Engineering Education},
%  volume={34},
%  number={4},
%  pages={339--347},
%  year={2009},
%  publisher={Taylor \& Francis}
% }

% @article{marton2005unit,
%  title={On the unit of description in phenomenography},
%  author={Marton, Ference and Pong, Wing Yan},
%  journal={Higher Education Rresearch \& Development},
%  volume={24},
%  number={4},
%  pages={335--348},
%  year={2005},
%  publisher={Taylor \& Francis}
% }
%@article{hazzan2003students,
%  title={How students attempt to reduce abstraction in the learning of %mathematics and in the learning of computer science},
%  author={Hazzan, Orit},
%  journal={Computer Science Education},
%  volume={13},
%  number={2},
%  pages={95--122},
%  year={2003},
%  publisher={Taylor \& Francis}
%}
%@book{marton1997learning,
%  title={Learning and awareness},
%  author={Marton, Ference and Booth, Shirley A},
%  year={1997},
%  publisher={Routledge}
%}
%@article{svensson1997theoretical,
%  title={Theoretical foundations of phenomenography},
%  author={Svensson, Lennart},
%  journal={Higher Education Research \& Development},
%  volume={16},
%  number={2},
%  pages={159--171},
%  year={1997},
%  publisher={Taylor \& Francis}
%}
@article{marton2005unit,
  title={On the unit of description in phenomenography},
  author={Marton, Ference and Pong, Wing Yan},
  journal={Higher education research \& development},
  volume={24},
  number={4},
  pages={335--348},
  year={2005},
  publisher={Taylor \& Francis}
}
@article{weber2004traditional,
  title={Traditional instruction in advanced mathematics courses: A case study of one professor’s lectures and proofs in an introductory real analysis course},
  author={Weber, Keith},
  journal={The Journal of Mathematical Behavior},
  volume={23},
  number={2},
  pages={115--133},
  year={2004},
  publisher={Elsevier}
}
@article{hazzan2003students,
  title={How students attempt to reduce abstraction in the learning of mathematics and in the learning of computer science},
  author={Hazzan, Orit},
  journal={Computer Science Education},
  volume={13},
  number={2},
  pages={95--122},
  year={2003},
  publisher={Taylor \& Francis}
}
@book{Mattuck,
author={Mattuck, Arthur},
year={1999},
title={Introduction to Analysis},
publisher={Prentice Hall}
}
@article{svensson1997theoretical,
  title={Theoretical foundations of phenomenography},
  author={Svensson, Lennart},
  journal={Higher Education Research \& Development},
  volume={16},
  number={2},
  pages={159--171},
  year={1997},
  publisher={Taylor \& Francis}
}
@article{moore1994making,
  title={Making the transition to formal proof},
  author={Moore, Robert C},
  journal={Educational Studies in mathematics},
  volume={27},
  number={3},
  pages={249--266},
  year={1994},
  publisher={Springer},
  annote={costs money}
}