According to Rule 16 of the Bluebook, periodicals include articles in:
Search Print & E-Journals and Library Catalog for title of a journal or law review. Use the library's Interlibrary Loan service to request an article not available in Pace collection.
Books from other Pace libraries (Mortola or Birnbaum)
Books via ConnectNY
Books in other libraries--use interlibrary loan
Opening statements (Law)