Callan Method

Callan Publishing Ltd

Callan Method 4                                  

Callan Method Student’s Book Stage 2: LESSON 10－24 including Vocabulary

Callan Method Student's book 2                  

Generico

CALLAN METHOD Book two Pupil's book              

Lean Startup Publishing

Recommendation of CALLAN method (Japanese Edition)

Zigzag English

40 INTERMEDIATE BUSINESS ENGLISH DIALOGUES: Business English Conversation, English at Work - B1, B2