The UNDL Foundation invites submissions to the first volume of the UNL Series, a publication dedicated to technical issues of the UNL. The volume, to be released in May 2013, will be devoted to the lexical aspects of UNL, and will include invited papers from the participants in the I UNL Panel, as well as selected papers from any researchers from inside and outside the UNL Community. The deadline for the submissions is February 15th.

The UNL is an artificial language used to represent and process information across language barriers. Created by the Institute of Advanced Studies of the United Nations University, in Tokyo, Japan, in 1996, the UNL has been used for several different tasks in natural language processing, especially in machine translation and information retrieval. In the UNL approach, information conveyed by natural languages is represented as a graph structure in which nodes stand for concepts and where edges denote binary semantic relations between concepts. The nodes in the UNL graph are called "Universal Words" (or simply UW's) and may be specified by a predefined set of attributes. The set of relations is also predefined in the UNL specifications and currently consists of 46 semantic cases (such as agent, object, place, time and instrument) and other set theory relations (such as conjunction, disjunction and inclusion).

Presently developed by the UNDL Foundation, in Geneva, Switzerland, under a mandate of the United Nations, the UNL, which was originally proposed more than 15 years ago, has been currently undergoing an in-depth and comprehensive revision, in which researchers from inside and outside the UNL Community are invited to participate. In order to organize the discussion about the necessary changes and updates to the present specifications, the UNDL Foundation invites submissions about the lexical aspects of the UNL. This was the object of the I UNL Panel, which took place in Mumbai on Dec 15th, as an associated event to Coling 2012, and this is now the object of the first volume of UNL Series, to be published next May, and for which we request contributions in the form of papers addressing any or all the questions referred to below:

• What is to be considered a "Universal Word"?
• Which named entities should be introduced in the dictionary of UW's, if any?
• UW's must correspond to roots, to stems or to word forms?
• Antonyms should be represented as a single UW or as different UW's?
• When a multiword expression must be represented as a UW?

These topics illustrate theoretical and practical issues concerning UW's and have been receiving several different possible answers inside the UNL Community. The main goal of this first volume of the UNL Series is to discuss which answers would be more appropriate and feasible, considering the nature and role of the UNL, and the state of the art of the theory and technology on natural language processing. Participants may discuss particular cases as starting points for their presentations, but we would expect them to suggest some general procedures to be adopted, which may either confirm or deny our current practices, which have been object of revision. Participants should understand, however, that only the structure of UNL is under discussion. The commitments, assumptions and properties of the UNL (described at www.unlweb.net/wiki/UNL), which are the keystones of the language, should be taken for granted, and are expected to be used as the general framework for all answers.

The specialists are requested to explain their positions in a paper in a question-answer format, with 5 to 30 pages, according to the instructions below. The participation is open to the whole community, including those that are not registered at the www.unlweb.net or that did not participate in the I UNL Panel. The draft version of the papers should be sent to This e-mail address is being protected from spambots. You need JavaScript enabled to view it before February 15th, 2013, and will be reviewed by the editors, which will select the best papers for publication in a book planned to be released by May 2013.

For further instructions, please refer to www.unlweb.net/book or write to This e-mail address is being protected from spambots. You need JavaScript enabled to view it .