diff --git a/CHANGELOG.md b/CHANGELOG.md
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+++ b/CHANGELOG.md
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+# Revision history for birds-of-paradise
+
+## 0.1.0.0 -- 2020-05-19
+
+* First chirping.
diff --git a/LICENSE b/LICENSE
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--- /dev/null
+++ b/LICENSE
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+Copyright (c) 2020, cutsea110
+
+All rights reserved.
+
+Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following conditions are met:
+
+    * Redistributions of source code must retain the above copyright
+      notice, this list of conditions and the following disclaimer.
+
+    * Redistributions in binary form must reproduce the above
+      copyright notice, this list of conditions and the following
+      disclaimer in the documentation and/or other materials provided
+      with the distribution.
+
+    * Neither the name of cutsea110 nor the names of other
+      contributors may be used to endorse or promote products derived
+      from this software without specific prior written permission.
+
+THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+"AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
diff --git a/Setup.hs b/Setup.hs
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+++ b/Setup.hs
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+import Distribution.Simple
+main = defaultMain
diff --git a/birds-of-paradise.cabal b/birds-of-paradise.cabal
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--- /dev/null
+++ b/birds-of-paradise.cabal
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+cabal-version:       2.4
+-- Initial package description 'birds-of-paradise.cabal' generated by
+-- 'cabal init'.  For further documentation, see
+-- http://haskell.org/cabal/users-guide/
+
+name:                birds-of-paradise
+version:             0.1.0.0
+synopsis:            Birds of Paradise
+description:         Birds of Paradise is yet another SK combinator library.
+homepage:            https://github.com/cutsea110/birds-of-paradise.git
+-- bug-reports:
+license:             BSD-3-Clause
+license-file:        LICENSE
+author:              cutsea110
+maintainer:          cutsea110@gmail.com
+-- copyright:
+category:            Language
+extra-source-files:  CHANGELOG.md
+
+library
+  exposed-modules:     Data.Function.Combinator.Birds
+  -- other-modules:
+  -- other-extensions:
+  build-depends:       base ^>=4.12.0.0
+  hs-source-dirs:      src
+  default-language:    Haskell2010
+  ghc-options:         -Wall
+
+test-suite birds-of-paradise-test
+  default-language:    Haskell2010
+  type:                exitcode-stdio-1.0
+  hs-source-dirs:      test
+  main-is:             MyLibTest.hs
+  build-depends:       base ^>=4.12.0.0
diff --git a/src/Data/Function/Combinator/Birds.hs b/src/Data/Function/Combinator/Birds.hs
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--- /dev/null
+++ b/src/Data/Function/Combinator/Birds.hs
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+module Data.Function.Combinator.Birds
+  ( bluebird
+  , blackbird
+  , bunting
+  , becard
+  , cardinal
+  , dove
+  , dickcissel
+  , dovekies
+  , eagle
+  , baldEagle
+  , finch
+  , goldFinch
+  , hummingbird
+  , idiot
+  , jay
+  , kestrel
+  , lark
+  , mockingbird
+  , doubleMockingbird
+  , owl
+  , queerbird
+  , quixoticbird
+  , quizzicalbird
+  , quirkybird
+  , quackybird
+  , robin
+  , starling
+  , thrush
+  , turing
+  , vireo
+  , warbler
+  , converseWarbler
+  , whybird
+  
+  , idiot'
+  , warbler'
+  , cardinal'
+  , robin'
+  , finch'
+  , vireo'
+  , idiot''
+  , warbler''
+  , cardinal''
+  , robin''
+  , finch''
+  , vireo''
+
+  , kite
+  -- , omega
+  , konstantMocker
+  , crossedKonstantMocker
+  , theta
+  ) where
+
+import Unsafe.Coerce (unsafeCoerce)
+
+-- | B
+bluebird :: (b -> c) -> (a -> b) -> a -> c
+bluebird f g x = f (g x)
+
+-- | B1
+blackbird :: (c -> d) -> (a -> b -> c) -> a -> b -> d
+blackbird f g x y = f (g x y)
+
+-- | B2
+bunting :: (d -> e) -> (a -> b -> c -> d) -> a -> b -> c -> e
+bunting f g x y z = f (g x y z)
+
+-- | B3
+becard :: (c -> d) -> (b -> c) -> (a -> b) -> a -> d
+becard f g h x = f (g ( h x))
+
+-- | C
+cardinal :: (a -> b -> c) -> b -> a -> c
+cardinal f x y = f y x
+
+-- | D
+dove :: (a -> c -> d) -> a -> (b -> c) -> b -> d
+dove f x g y = f x (g y)
+
+-- | D1
+dickcissel :: (a -> b -> c -> d) -> a -> b -> (e -> c) -> e -> d
+dickcissel f x y g z = f x y (g z)
+
+-- | D2
+dovekies :: (a -> b -> c) -> (d -> a) -> d -> (e -> b) -> e -> c
+dovekies f g x h y = f (g x) (h y)
+
+-- | E
+eagle :: (a -> b -> c) -> a -> (d -> e -> b) -> d -> e -> c
+eagle f x g y z = f x (g y z)
+
+-- | E^
+baldEagle :: (a -> b -> c) -> (d -> e -> a) -> d -> e -> (f -> g -> b) -> f -> g -> c
+baldEagle f g x y h v w = f (g x y) (h v w)
+
+-- | F
+finch :: b -> a -> (a -> b -> c) -> c
+finch x y f = f y x
+
+-- | G
+goldFinch :: (a -> b -> c) -> (d -> b) -> d -> a -> c
+goldFinch f g x y = f y (g x)
+
+-- | H
+hummingbird :: (a -> b -> a -> c) -> a -> b -> c
+hummingbird f x y = f x y x
+
+-- | I
+idiot :: a -> a
+idiot x = x
+
+-- | J
+jay :: (a -> b -> b) -> a -> a -> b -> b
+jay f x y z = f x (f y z)
+
+-- | K
+kestrel :: a -> b -> a
+kestrel x _ = x
+
+-- | L
+lark :: (b -> c) -> (a -> b) -> c
+lark f g = f (g g') where g' = unsafeCoerce g
+
+-- | M
+mockingbird :: (a -> b) -> b
+mockingbird x = x x' where x' = unsafeCoerce x
+
+-- | M2
+doubleMockingbird :: (a -> b -> c) -> a -> c
+doubleMockingbird f x = mockingbird (f x)
+
+-- | O
+owl :: ((a -> b) -> a) -> (a -> b) -> b
+owl f g = g (f g)
+
+-- | Q
+queerbird :: (a -> b) -> (b -> c) -> a -> c
+queerbird f g x = g (f x)
+
+-- | Q1
+quixoticbird :: (a -> b) -> c -> (c -> a) -> b
+quixoticbird f x g = f (g x)
+
+-- | Q2
+quizzicalbird :: a -> (b -> c) -> (a -> b) -> c
+quizzicalbird x f g = f (g x)
+
+-- | Q3
+quirkybird :: (a -> b) -> a -> (b -> c) -> c
+quirkybird f x g = g (f x)
+
+-- | Q4
+quackybird :: a -> (a -> b) -> (b -> c) -> c
+quackybird x f g = g (f x)
+
+-- | R
+robin :: b -> (a -> b -> c) -> a -> c
+robin x f y = f y x
+
+-- | S
+starling :: (a -> b -> c) -> (a -> b) -> a -> c
+starling f g x = f x (g x)
+
+-- | T
+thrush :: a -> (a -> b) -> b
+thrush x f = f x
+
+-- | U
+turing :: (a -> (b -> c) -> b) -> (b -> c) -> c
+turing f g = g (f f' g) where f' = unsafeCoerce f
+
+-- | V
+vireo :: a -> b -> (a -> b -> c) -> c
+vireo x y f = f x y
+
+-- | W
+warbler :: (a -> a -> b) -> a -> b
+warbler f x = f x x
+
+-- | W1
+converseWarbler :: a -> (a -> a -> b) -> b
+converseWarbler = cardinal warbler
+
+-- | Y
+whybird :: (x -> x) -> x
+whybird x = x (whybird x)
+
+-- | I*
+idiot' :: ((a -> b) -> a) -> (a -> b) -> a
+idiot' f g = f g
+
+-- | W*
+warbler' :: (a -> b -> b -> c) -> a -> b -> c
+warbler' f x y = f x y y
+
+-- | C*
+cardinal' :: (a -> b -> c -> d) -> a -> c -> b -> d
+cardinal' f x y z = f x z y
+
+-- | R*
+robin' :: (a -> b -> c -> d) -> c -> a -> b -> d
+robin' f x y z = f y z x
+
+-- | F*
+finch' :: (a -> b -> c -> d) -> c -> b -> a -> d
+finch' f x y z = f z y x
+
+-- | V*
+vireo' :: (a -> b -> c -> d) -> b -> a -> c -> d
+vireo' f x y z = f y x z
+
+-- | I**
+idiot'' :: (a -> b -> c) -> a -> b -> c
+idiot'' f g h =  f g h
+
+-- | W**
+warbler'' :: (a -> b -> c -> c -> d) -> a -> b -> c -> d
+warbler'' f x y z = f x y z z
+
+-- | C**
+cardinal'' :: (a -> b -> c -> d -> e) -> a -> b -> d -> c -> e
+cardinal'' f x y z w = f x y w z
+
+-- | R**
+robin'' :: (a -> b -> c -> d -> e) -> a -> d -> b -> c -> e
+robin'' f x y z w = f x z w y
+
+-- | F**
+finch'' :: (a -> b -> c -> d -> e) -> a -> d -> c -> b -> e
+finch'' f x y z w = f x w z y
+
+-- | V**
+vireo'' :: (a -> b -> c -> d -> e) -> a -> c -> d -> b -> e
+vireo'' f x y z w = f x w y z
+
+-- | KI
+kite :: a -> b -> b
+kite _ y = y
+
+-- FIXME: Omega is missing because it will fail to compile. :-(
+-- | Omega
+-- omega :: a
+-- omega = mockingbird mockingbird
+
+-- | KM
+konstantMocker :: c -> (a -> b) -> b
+konstantMocker = kestrel mockingbird
+
+-- | C(KM)
+crossedKonstantMocker :: (a -> b) -> c -> b
+crossedKonstantMocker = cardinal konstantMocker
+
+-- | Theta
+theta :: (a -> a) -> a
+theta = whybird owl
diff --git a/test/MyLibTest.hs b/test/MyLibTest.hs
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+++ b/test/MyLibTest.hs
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+module Main (main) where
+
+main :: IO ()
+main = putStrLn "Test suite not yet implemented."