Dr. Montessori's Own Handbook — Maria Montessori
Pedagogical Anthropology — Maria Montessori
Spontaneous Activity in Education — Maria Montessori
The Montessori Elementary Material / The Advanced Montessori Method — Maria Montessori
The Montessori Method / Scientific Pedagogy as Applied to Child Education in 'The Children's Houses' with Additions and Revisions by the Author — Maria Montessori