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It looks at least like Doris sp. 4 at page 156 in IPN
Gosliner, Terrence M., David W. Behrens & Ángel Valdés. 2008. Indo-Pacific Nudibranchs and Sea Slugs. Sea Challengers Natural History Books.
Gig Harbor, Washington. 426pp.
Let me quote the description:" This species can be easily recognized by its yellow body with rounded tubercles where some are tipped with black pigment. The gill also contain black pigment while the rhinophores are yellow."
This species or a pretty similar one was the 'Opisthobranch of the Week' at Michael D.Miller's Slug Site on 09 June 2008