kinda hard to find - because its about how you speak / how it sounds
[quote]It is similar to the Korean r. To an English speaker’s ears, its pronunciation varies between a flapped d ([ɾ], as in American English buddy)
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I’m still studying japanese, until I JLPT 2 I guess
But yeah try it, next time when you talk to a Japanese person pronounce it subtle starting with a D instead of R, they can’t tell a difference =D
For example: Watashi no ryuu, as in 流 … ryuu, lyuu, dyuu - all the same, you can pronounce it the way you want
again - not a rule or anything, just phonology I guess