"Textbook evaluation"@en . . "Fiene Bredow" . "Cognitive unity"@en . "Process-product duality"@en . "e96b3d4eca9332c9c1afcff4f6a70cb5" . . "Teacher influence"@en . "Symbolic language"@en . "Mathematical argumentation"@en . . "Epistemology"@en . "Mathematics teachers"@en . "Bredow" . "Algebra"@en . "Classroom research"@en . "Proof"@en . "Interdisciplinary approach"@en . "Argumentation"@en . "Fiene" .