Libros de mental arithmetic

Juvenile mental arithmetic

Rapid figuring

New mental arithmetic

Primary exercises in mental arithmetic for seventh year

A Mental Arithmetic Upon the Inductive Plan: Being an Advanced Intellectual Course, Designed for ..

Mental arithmetic, part II

Robinson's Progressive intellectual arithmetic

The art of ready reckoning, or, Mental and practical arithmetic

Grummett's Canada calculator

New mental arithmetic, by John Duncan. [1st ed.], 7th and revised impression ; revised by Helen Cline

Matematicas Sencillas / Doing Simple Math in Your Head

Mental arithmetic

100 Mental Maths Starters Year 3 (100 Mental Maths Starters)

Mental mathematics for the numeracy hour

Intellectual arithmetic