The Aural System :
Hardy, Charles
The Aural System : Being the Most Direct, the Straight-Line Method for the Simultaneous Fourfold Mastery of a Foreign Language. [electronic resource] / Charles Hardy - Project Gutenberg, 2009 - Project Gutenberg 29163 .
Public domain in the USA.
Electronic text
Languages, Modern -- Study and teaching
LB PB
The Aural System : Being the Most Direct, the Straight-Line Method for the Simultaneous Fourfold Mastery of a Foreign Language. [electronic resource] / Charles Hardy - Project Gutenberg, 2009 - Project Gutenberg 29163 .
Public domain in the USA.
Electronic text
Languages, Modern -- Study and teaching
LB PB