All command line field values are case sensitive:

Field Command Line Value Alternative
Command Line
Abstract ab= abstract=
Affiliation aff=
Age Group ag=
Author au= author=
Author of Reviewed Item aur=
Auxiliary materials aux=
Book Title bt= booktitle=
Book Type bty= booktype
Classification Code cc= class=
Conference conf= conference=
Content Owner co=
Content Owner Type cot=
Copyright Holder CopyrightHolder=
Copyright Statement CopyrightStatement=
Copyright Year CopyrightYear=
Document Type dt= doc=
DOI Number doi=
Full Text ft=
Index Term it= indexterm=
ISBN isbn-
ISSN issn=
Issue issue=
Issue Publication Date IssuePublicationDate=
Journal Title jt= journaltitle=
Keywords (just the KW field, not Title & Index Term) kw= keyword=
Keywords (TI, IT & KW) KEYWORDS=
Language lang=
Location loc=
Methodology me= methodology=
Population Group pg= pop=
Publication Date PublicationDate=
Publication History PublicationHistory=
Publication Status PublicationStatus=
Publication Year py= pubyr=
Publisher pub= publisher=
Release Date rd=
Reviewed Item rev=
Test & Measures tm=
Title ti= title=
Title of Reviewed Item tr=
Year of Reviewed Item yrrev=
UID uid=