Imports a New Economics Papers-Message from the REPEC-NEP Service.

RePEc (Research Papers in Economics) is a collaborative effort of over 100 volunteers in 49 countries to enhance the dissemination of research in economics. The heart of the project is a decentralized database of working papers, journal articles and software components. All RePEc material is freely available.

At the time of writing RePEc holds over 300.000 items.

NEP (New Economic Papers) is an announcement service which filters information on new additions to RePEc into edited reports. The goal is to provide subscribers with up-to-date information to the research literature.

This importer is capable of importing NEP messages into JabRef.

There is no officially defined message format for NEP. NEP messages are assumed to have (and almost always have) the form given by the following semi-formal grammar:

NEPMessage:
      MessageSection NEPMessage
      MessageSection

MessageSection:
      OverviewMessageSection
      OtherMessageSection

# we skip the overview
OverviewMessageSection:
      'In this issue we have: ' SectionSeparator OtherStuff

OtherMessageSection:
      SectionSeparator  OtherMessageSectionContent

# we skip other stuff and read only full working paper references
OtherMessageSectionContent:
      WorkingPaper EmptyLine OtherMessageSectionContent
      OtherStuff EmptyLine OtherMessageSectionContent
      ''

OtherStuff:
      NonEmptyLine OtherStuff
      NonEmptyLine

NonEmptyLine:
      a non-empty String that does not start with a number followed by a '.'

# working papers are recognized by a number followed by a '.'
# in a non-overview section
WorkingPaper:
      Number'.' WhiteSpace TitleString EmptyLine Authors EmptyLine Abstract AdditionalFields
      Number'.' WhiteSpace TitleString AdditionalFields Abstract AdditionalFields

TitleString:
      a String that may span several lines and should be joined

# there must be at least one author
Authors:
      Author '\n' Authors
      Author '\n'

# optionally, an institution is given for an author
Author:
      AuthorName
      AuthorName '(' Institution ')'

# there are no rules about the name, it may be firstname lastname or lastname, firstname or anything else
AuthorName:
      a non-empty String without '(' or ')' characters, not spanning more that one line

Institution:
      a non-empty String that may span several lines

Abstract:
      a (possibly empty) String that may span several lines

AdditionalFields:
      AdditionalField '\n' AdditionalFields
      EmptyLine AdditionalFields
      ''

AdditionalField:
      'Keywords:' KeywordList
      'URL:' non-empty String
      'Date:' DateString
      'JEL:' JelClassificationList
      'By': Authors

KeywordList:
       Keyword ',' KeywordList
       Keyword ';' KeywordList
       Keyword

Keyword:
       non-empty String that does not contain ',' (may contain whitespace)

# if no date is given, the current year as given by the system clock is assumed
DateString:
       'yyyy-MM-dd'
       'yyyy-MM'
       'yyyy'

JelClassificationList:
       JelClassification JelClassificationList
       JelClassification

# the JEL Classifications are set into a new BIBTEX-field 'jel'
# they will appear if you add it as a field to one of the BIBTex Entry sections
JelClassification:
       one of the allowed classes, see http://ideas.repec.org/j/

SectionSeparator:
      '\n-----------------------------'