Japanese version available here. Both English and Japanese versions are fully charted using standard knitting and/or crochet symbols.

child size:

• Japanese size 10/0 crochet hook (6.0mm) (The pattern actually says Japanese 15/0 crochet hook, but there is no such size, so it must be a typo.)
• 65g (92.6m) yarn
• gauge: in double crochet, 9.5 st and 4.5 rows in 10cm square

adult size:

• 7mm crochet hook
• 85g (121.1m) yarn
• gauge: in double crochet, 10 st and 5.5 rows in 10cm square

Note that gauge and hook size are different for the child size and adult size.