Cita APA (7th ed.)

PARRAGON BOOKS LTD. (2017). SELF- IMPROVEMENT PUZZLES BRAIN- BOOSTING CHALLENGES: PRACTICAL PUZZLES TO TRAIN YOUR BRAIN & IMPROVE YOUR MEMORY. PARRAGON BOOKS LTD.

Cita Chicago (17th ed.)

PARRAGON BOOKS LTD. SELF- IMPROVEMENT PUZZLES BRAIN- BOOSTING CHALLENGES: PRACTICAL PUZZLES TO TRAIN YOUR BRAIN & IMPROVE YOUR MEMORY. NEW YORK: PARRAGON BOOKS LTD, 2017.

Cita MLA (9th ed.)

PARRAGON BOOKS LTD. SELF- IMPROVEMENT PUZZLES BRAIN- BOOSTING CHALLENGES: PRACTICAL PUZZLES TO TRAIN YOUR BRAIN & IMPROVE YOUR MEMORY. PARRAGON BOOKS LTD, 2017.

Atenció: Aquestes cites poden no estar 100% correctes.