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Trade and Private International Law LLM Long Paper Writing Group


I created this guide to inform you about research materials that I think will be helpful for your paper topics.  My intention was to focus on the topic ideas that have been presented to me by the group thus far.

The guide contains the following information:

  • Links to other Harvard Library research guides with helpful information for LLMs
  • Information about how to find books by subject in the HOLLIS library catalog, using (a) call numbers, (b) established subject terms, and (c) book series titles
  • A list of journal databases and indexes

As the librarian liaison for your group, you are welcome to contact me directly for help with your research.  My contact information is at the top of this screen.

Other Harvard Library Research Guides

I have attempted to include in this guide only information that is not duplicated in our other guides.  Therefore, you may find the guides listed below useful as you work with the library's resources to research your papers.

IMPORTANT: For Arbitration Researchers

The law library's research guide for international arbitration was updated very recently and it is available at

The international arbitration research guide covers how to use the library's print materials and subscription databases to find arbitration treaties, rules, awards, and commentary.  Both commercial and trade arbitration are considered.

To avoid duplication, this guide for your LLM writing group will not feature information about arbitration research.  

Books by Subject: Library of Congress Call Number System

The library uses the Library of Congress Call Number System (, which is organized by subject, to assign call numbers to its materials. 

Under this system, books about law have call numbers that begin with the letter K:  

  • A call number that starts with "K" alone means that the book is about law in general.
  • There are jurisdictional "subclasses" within K; for example, books with call numbers that start with "KF" are about United States law.
  • Another important subclass is "KZ" which designates materials about international law.

Following the class/sub-class indicator in the call number is a number that indicates the subject of the book.

The Library of Congress Classification Outline for Class K materials is at

As you can see from this list, materials on topics of interest to this group are in the following call number ranges:

  • Commercial Law: K1000-1395
  • Arbitration and Award: K2400-2405
  • Regulation of Industry, Trade, and Commerce: K3840-4375
  • Private International Law / Conflict of Laws: K7000-7720


Why are call numbers important for research?

Only a percentage of the law library's materials are physically here in the law library building.  Most of them are in an offsite storage location.  In addition, several other Harvard libraries have materials related to law.

If you go to the law library's main reading room and look at the shelves with books whose call numbers start with K3840, you will only see a portion of Harvard's books on the international trade law and regulation.


How can HOLLIS help?

You can browse by call number across the entire Harvard Library collection, including HD, electronically through Hollis.

On the HOLLIS homepage, click Starts With / Browse at the top of the screen.  Select the option to Browse by Call Number - Library of Congress, enter K3840 in the search box, and press Return.

Books by Subject: Searching HOLLIS Using Subject Terms

In addition to its call number system, the Library of Congress has created a controlled vocabulary to describe subjects in catalog records for library materials.  Many catalog records in HOLLIS include these controlled, predefined vocabulary terms, which are called Library of Congress Subject Headings (LCSH) (, in the Subject field.  Although there are also other lists of subject terms that catalogers also use, the LCSH list predominates in the HOLLIS catalog, especially in records for newer materials.

Using subject terms from a controlled vocabulary like LCSH to search for materials in HOLLIS can be especially helpful to comparative law researchers who want, in a single search, to find materials in several different languages that all discuss the same subject.  Researchers may also find that subject searches return more accurate results than general keyword searches.

Below are links to some sample HOLLIS searches by subject, using LCSH and other predefined subject terms. 

The searches are meant to be quite broad. To limit the displayed search results, you can edit the search to add additional keywords, and/or you can use the limiting options on the right side of the HOLLIS search results screen.

Journal Databases and Indexes

Use periodical indexes and databases to find relevant scholarly articles for your topic. Those listed below focus on the social sciences, including law, political science, economics, and other areas that will be of interest to people in this group.

Note that some indexes only provide citations to articles.  For those, you will need to search for the journal title in HOLLIS to learn which database(s) we subscribe to that provide access to the journal.

To search for a subscription database that is not listed below, visit

Other Electronic Sources