@unpublished{repository840,
       publisher = {Journal of Physics: Conference Series},
           title = {Similarity "Obstacles in Constructing Geometrical Proofs of Mathematics-Teacher-Students Based on Boero's Proving Model"},
            note = {Unpublished},
          author = {Samsul, SMF},
             url = {http://repository.uhamka.ac.id/id/eprint/840/}
}