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diff --git a/src/Text/Pandoc/HtmlEntities.hs b/src/Text/Pandoc/HtmlEntities.hs
new file mode 100644
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+++ b/src/Text/Pandoc/HtmlEntities.hs
@@ -0,0 +1,306 @@
+-- | Functions for encoding unicode characters as HTML entity 
+-- references, and vice versa.
+module Text.Pandoc.HtmlEntities (
+                     htmlEntityToChar,
+                     charToHtmlEntity,
+                     decodeEntities,
+                     encodeEntities
+                    ) where
+import Char ( chr, ord )
+import Text.Regex ( mkRegex, matchRegexAll )
+import Maybe ( fromMaybe )
+
+-- regexs for entities
+decimalCodedEntity = mkRegex "&#([0-9]+);"
+characterEntity = mkRegex "&#[0-9]+;|&[A-Za-z0-9]+;"
+
+-- | Return a string with all entity references decoded to unicode characters
+-- where possible.  
+decodeEntities :: String -> String
+decodeEntities str = 
+  case (matchRegexAll characterEntity str) of
+    Nothing -> str
+    Just (before, match, rest, _) -> before ++ replacement ++ (decodeEntities rest)
+      where replacement = case (htmlEntityToChar match) of
+                            Just ch -> [ch]
+                            Nothing -> match
+
+-- | Returns a string with characters replaced with entity references where possible.
+encodeEntities :: String -> String
+encodeEntities = concatMap (\c -> fromMaybe [c] (charToHtmlEntity c)) 
+
+-- | If the string is a valid entity reference, returns @Just@ the character,
+-- otherwise @Nothing@.
+htmlEntityToChar :: String -> Maybe Char 
+htmlEntityToChar entity = 
+    case (lookup entity htmlEntityTable) of
+      Just ch -> Just ch
+      Nothing -> case (matchRegexAll decimalCodedEntity entity) of
+                   Just (_, _, _, [sub]) -> Just (chr (read sub))
+                   Nothing               -> Nothing
+
+-- | If there is an entity reference corresponding to the character, returns
+-- @Just@ the entity reference, otherwise @Nothing@.
+charToHtmlEntity :: Char -> Maybe String
+charToHtmlEntity char = 
+    let matches = filter (\(entity, character) -> (character == char)) htmlEntityTable in
+    if (length matches) == 0 then
+        Nothing
+    else
+        Just (fst (head matches))
+
+htmlEntityTable :: [(String, Char)]
+htmlEntityTable =  [
+	(""", chr 34),
+	("&", chr 38),
+	("<", chr 60),
+	(">", chr 62),
+	(" ", chr 160),
+	("¡", chr 161),
+	("¢", chr 162),
+	("£", chr 163),
+	("¤", chr 164),
+	("¥", chr 165),
+	("¦", chr 166),
+	("§", chr 167),
+	("¨", chr 168),
+	("©", chr 169),
+	("ª", chr 170),
+	("«", chr 171),
+	("¬", chr 172),
+	("­", chr 173),
+	("®", chr 174),
+	("¯", chr 175),
+	("°", chr 176),
+	("±", chr 177),
+	("²", chr 178),
+	("³", chr 179),
+	("´", chr 180),
+	("µ", chr 181),
+	("¶", chr 182),
+	("·", chr 183),
+	("¸", chr 184),
+	("¹", chr 185),
+	("º", chr 186),
+	("»", chr 187),
+	("¼", chr 188),
+	("½", chr 189),
+	("¾", chr 190),
+	("¿", chr 191),
+	("À", chr 192),
+	("Á", chr 193),
+	("Â", chr 194),
+	("Ã", chr 195),
+	("Ä", chr 196),
+	("Å", chr 197),
+	("Æ", chr 198),
+	("Ç", chr 199),
+	("È", chr 200),
+	("É", chr 201),
+	("Ê", chr 202),
+	("Ë", chr 203),
+	("Ì", chr 204),
+	("Í", chr 205),
+	("Î", chr 206),
+	("Ï", chr 207),
+	("Ð", chr 208),
+	("Ñ", chr 209),
+	("Ò", chr 210),
+	("Ó", chr 211),
+	("Ô", chr 212),
+	("Õ", chr 213),
+	("Ö", chr 214),
+	("×", chr 215),
+	("Ø", chr 216),
+	("Ù", chr 217),
+	("Ú", chr 218),
+	("Û", chr 219),
+	("Ü", chr 220),
+	("Ý", chr 221),
+	("Þ", chr 222),
+	("ß", chr 223),
+	("à", chr 224),
+	("á", chr 225),
+	("â", chr 226),
+	("ã", chr 227),
+	("ä", chr 228),
+	("å", chr 229),
+	("æ", chr 230),
+	("ç", chr 231),
+	("è", chr 232),
+	("é", chr 233),
+	("ê", chr 234),
+	("ë", chr 235),
+	("ì", chr 236),
+	("í", chr 237),
+	("î", chr 238),
+	("ï", chr 239),
+	("ð", chr 240),
+	("ñ", chr 241),
+	("ò", chr 242),
+	("ó", chr 243),
+	("ô", chr 244),
+	("õ", chr 245),
+	("ö", chr 246),
+	("÷", chr 247),
+	("ø", chr 248),
+	("ù", chr 249),
+	("ú", chr 250),
+	("û", chr 251),
+	("ü", chr 252),
+	("ý", chr 253),
+	("þ", chr 254),
+	("ÿ", chr 255),
+	("Œ", chr 338),
+	("œ", chr 339),
+	("Š", chr 352),
+	("š", chr 353),
+	("Ÿ", chr 376),
+	("ƒ", chr 402),
+	("ˆ", chr 710),
+	("˜", chr 732),
+	("Α", chr 913),
+	("Β", chr 914),
+	("Γ", chr 915),
+	("Δ", chr 916),
+	("Ε", chr 917),
+	("Ζ", chr 918),
+	("Η", chr 919),
+	("Θ", chr 920),
+	("Ι", chr 921),
+	("Κ", chr 922),
+	("Λ", chr 923),
+	("Μ", chr 924),
+	("Ν", chr 925),
+	("Ξ", chr 926),
+	("Ο", chr 927),
+	("Π", chr 928),
+	("Ρ", chr 929),
+	("Σ", chr 931),
+	("Τ", chr 932),
+	("Υ", chr 933),
+	("Φ", chr 934),
+	("Χ", chr 935),
+	("Ψ", chr 936),
+	("Ω", chr 937),
+	("α", chr 945),
+	("β", chr 946),
+	("γ", chr 947),
+	("δ", chr 948),
+	("ε", chr 949),
+	("ζ", chr 950),
+	("η", chr 951),
+	("θ", chr 952),
+	("ι", chr 953),
+	("κ", chr 954),
+	("λ", chr 955),
+	("μ", chr 956),
+	("ν", chr 957),
+	("ξ", chr 958),
+	("ο", chr 959),
+	("π", chr 960),
+	("ρ", chr 961),
+	("ς", chr 962),
+	("σ", chr 963),
+	("τ", chr 964),
+	("υ", chr 965),
+	("φ", chr 966),
+	("χ", chr 967),
+	("ψ", chr 968),
+	("ω", chr 969),
+	("ϑ", chr 977),
+	("ϒ", chr 978),
+	("ϖ", chr 982),
+	(" ", chr 8194),
+	(" ", chr 8195),
+	(" ", chr 8201),
+	("‌", chr 8204),
+	("‍", chr 8205),
+	("‎", chr 8206),
+	("‏", chr 8207),
+	("–", chr 8211),
+	("—", chr 8212),
+	("‘", chr 8216),
+	("’", chr 8217),
+	("‚", chr 8218),
+	("“", chr 8220),
+	("”", chr 8221),
+	("„", chr 8222),
+	("†", chr 8224),
+	("‡", chr 8225),
+	("•", chr 8226),
+	("…", chr 8230),
+	("‰", chr 8240),
+	("′", chr 8242),
+	("″", chr 8243),
+	("‹", chr 8249),
+	("›", chr 8250),
+	("‾", chr 8254),
+	("⁄", chr 8260),
+	("€", chr 8364),
+	("ℑ", chr 8465),
+	("℘", chr 8472),
+	("ℜ", chr 8476),
+	("™", chr 8482),
+	("ℵ", chr 8501),
+	("←", chr 8592),
+	("↑", chr 8593),
+	("→", chr 8594),
+	("↓", chr 8595),
+	("↔", chr 8596),
+	("↵", chr 8629),
+	("⇐", chr 8656),
+	("⇑", chr 8657),
+	("⇒", chr 8658),
+	("⇓", chr 8659),
+	("⇔", chr 8660),
+	("∀", chr 8704),
+	("∂", chr 8706),
+	("∃", chr 8707),
+	("∅", chr 8709),
+	("∇", chr 8711),
+	("∈", chr 8712),
+	("∉", chr 8713),
+	("∋", chr 8715),
+	("∏", chr 8719),
+	("∑", chr 8721),
+	("−", chr 8722),
+	("∗", chr 8727),
+	("√", chr 8730),
+	("∝", chr 8733),
+	("∞", chr 8734),
+	("∠", chr 8736),
+	("∧", chr 8743),
+	("∨", chr 8744),
+	("∩", chr 8745),
+	("∪", chr 8746),
+	("∫", chr 8747),
+	("∴", chr 8756),
+	("∼", chr 8764),
+	("≅", chr 8773),
+	("≈", chr 8776),
+	("≠", chr 8800),
+	("≡", chr 8801),
+	("≤", chr 8804),
+	("≥", chr 8805),
+	("⊂", chr 8834),
+	("⊃", chr 8835),
+	("⊄", chr 8836),
+	("⊆", chr 8838),
+	("⊇", chr 8839),
+	("⊕", chr 8853),
+	("⊗", chr 8855),
+	("⊥", chr 8869),
+	("⋅", chr 8901),
+	("⌈", chr 8968),
+	("⌉", chr 8969),
+	("⌊", chr 8970),
+	("⌋", chr 8971),
+	("⟨", chr 9001),
+	("⟩", chr 9002),
+	("◊", chr 9674),
+	("♠", chr 9824),
+	("♣", chr 9827),
+	("♥", chr 9829),
+	("♦", chr 9830)
+	]