Record individual study about Baltic, oddly (12)
I believe the answer is:
bibliography
'record' is the definition.
(a list of references in a scholarly work)
'individual study about baltic oddly' is the wordplay.
'individual study' becomes 'biography' (a study of a particular person).
'about' is an insertion indicator.
'oddly' indicates alternate letters (letters in the odd-numbered positions are used).
The alternate letters of 'baltic' are 'bli'.
'biography' placed around 'bli' is 'BIBLIOGRAPHY'.
(Other definitions for bibliography that I've seen before include "List of books on a subject" , "catalogue" .)