diff --git a/src/calibre/ebooks/metadata/__init__.py b/src/calibre/ebooks/metadata/__init__.py
index 3ee4ed33be..82f2ee40ea 100644
--- a/src/calibre/ebooks/metadata/__init__.py
+++ b/src/calibre/ebooks/metadata/__init__.py
@@ -53,8 +53,8 @@ def author_to_author_sort(author, method=None):
     if method == u'copy':
         return author
 
-    prefixes = set([x.lower() for x in tweaks['author_name_prefixes']])
-    prefixes |= set([x+u'.' for x in prefixes])
+    prefixes = set([y.lower() for y in tweaks['author_name_prefixes']])
+    prefixes |= set([y+u'.' for y in prefixes])
     while True:
         if not tokens:
             return author
@@ -64,8 +64,8 @@ def author_to_author_sort(author, method=None):
         else:
             break
 
-    suffixes = set([x.lower() for x in tweaks['author_name_suffixes']])
-    suffixes |= set([x+u'.' for x in suffixes])
+    suffixes = set([y.lower() for y in tweaks['author_name_suffixes']])
+    suffixes |= set([y+u'.' for y in suffixes])
 
     suffix = u''
     while True:
@@ -358,3 +358,12 @@ def check_isbn(isbn):
         return check_isbn13(isbn)
     return None
 
+def format_isbn(isbn):
+    cisbn = check_isbn(isbn)
+    if not cisbn:
+        return isbn
+    i = cisbn
+    if len(i) == 10:
+        return '-'.join((i[:2], i[2:6], i[6:9], i[9]))
+    return '-'.join((i[:3], i[3:5], i[5:9], i[9:12], i[12]))
+
diff --git a/src/calibre/library/catalogs/bibtex.py b/src/calibre/library/catalogs/bibtex.py
index b959f22eac..d87005f863 100644
--- a/src/calibre/library/catalogs/bibtex.py
+++ b/src/calibre/library/catalogs/bibtex.py
@@ -5,7 +5,7 @@ __license__   = 'GPL v3'
 __copyright__ = '2012, Kovid Goyal <kovid@kovidgoyal.net>'
 __docformat__ = 'restructuredtext en'
 
-import re, codecs
+import re, codecs, os
 from collections import namedtuple
 from types import StringType, UnicodeType
 
@@ -14,6 +14,7 @@ from calibre.customize import CatalogPlugin
 from calibre.library.catalogs import FIELDS, TEMPLATE_ALLOWED_FIELDS
 from calibre.customize.conversion import DummyReporter
 from calibre.constants import preferred_encoding
+from calibre.ebooks.metadata import format_isbn
 
 
 class BIBTEX(CatalogPlugin):
@@ -114,6 +115,8 @@ class BIBTEX(CatalogPlugin):
         from calibre.utils.date import now as nowf
         from calibre.utils.logging import default_log as log
 
+        library_name = os.path.basename(db.library_path)
+
         def create_bibtex_entry(entry, fields, mode, template_citation,
                                     bibtexdict, db, citation_bibtex=True, calibre_files=True):
 
@@ -142,6 +145,8 @@ class BIBTEX(CatalogPlugin):
                         item = repr(item)
                 elif field == 'title_sort':
                     item = entry['sort']
+                elif field == 'library_name':
+                    item = library_name
                 else:
                     item = entry[field]
 
@@ -183,7 +188,7 @@ class BIBTEX(CatalogPlugin):
 
                 elif field == 'isbn' :
                     # Could be 9, 10 or 13 digits
-                    bibtex_entry.append(u'isbn = "%s"' % re.sub(u'[0-9xX]', u'', item))
+                    bibtex_entry.append(u'isbn = "%s"' % format_isbn(item))
 
                 elif field == 'formats' :
                     #Add file path if format is selected
diff --git a/src/calibre/library/database2.py b/src/calibre/library/database2.py
index eed5ec173b..914de2358b 100644
--- a/src/calibre/library/database2.py
+++ b/src/calibre/library/database2.py
@@ -3626,7 +3626,6 @@ class LibraryDatabase2(LibraryDatabase, SchemaUpgrade, CustomColumns):
             if data['datatype'] == 'series':
                 FIELDS.add('%d_index'%x)
         data = []
-        library_name = os.path.basename(self.library_path)
         for record in self.data:
             if record is None: continue
             db_id = record[self.FIELD_MAP['id']]
@@ -3650,7 +3649,6 @@ class LibraryDatabase2(LibraryDatabase, SchemaUpgrade, CustomColumns):
             x['cover'] = os.path.join(path, 'cover.jpg')
             if not record[self.FIELD_MAP['cover']]:
                 x['cover'] = None
-            x['library_name'] = library_name
             formats = self.formats(record[self.FIELD_MAP['id']], index_is_id=True)
             if formats:
                 for fmt in formats.split(','):