Aikhenvald, Alexandra. The Manambu language of East Sepik, Papua New Guinea. 2008. hh:g:Aikhenvald:Manambu
Word-final voiceless plosives are unreleased except after long vowels. /v/ only contrasts with /p/ in word- and root-initial position, except in "a very slow register".
/pʷ bʷ/ can only occur word-finally or followed by /i ə/, but there's no contrast between /pʷə bʷə/ and /pu bu/.