diff --git a/docs/src/lib/binary_functions.md b/docs/src/lib/binary_functions.md
index a73b2d4107..b8e86c59cc 100644
--- a/docs/src/lib/binary_functions.md
+++ b/docs/src/lib/binary_functions.md
@@ -64,6 +64,7 @@ convex_hull(::SimpleSparsePolynomialZonotope, ::SimpleSparsePolynomialZonotope)
 ## Exact sum
 
 ```@docs
+⊞
 exact_sum(::SparsePolynomialZonotope, ::SparsePolynomialZonotope)
 ```
 
diff --git a/src/ConcreteOperations/exact_sum.jl b/src/ConcreteOperations/exact_sum.jl
index 42dc8b7465..0d25e7b623 100644
--- a/src/ConcreteOperations/exact_sum.jl
+++ b/src/ConcreteOperations/exact_sum.jl
@@ -12,12 +12,13 @@ Compute the exact sum of sparse polyomial zonotopes ``P₁`` and ``P₂``.
 
 ### Output
 
-exact sum ``P₁ ⊞ P₂``
-
+A `SparsePolynomialZonotope` representing the exact sum ``P₁ ⊞ P₂``.
 """
 function exact_sum(P1::SparsePolynomialZonotope, P2::SparsePolynomialZonotope)
 
-    indexvector(P1) == indexvector(P2) || throw(ArgumentError("Exact sum currently only implemented for Sparse Polynomial Zonotopes with the same index vector"))
+    indexvector(P1) == indexvector(P2) || throw(ArgumentError("the exact sum " *
+        "is currently only implemented for sparse polynomial zonotopes with " *
+        "the same index vector"))
 
     c = center(P1) + center(P2)
     G = hcat(genmat_dep(P1), genmat_dep(P2))
@@ -28,4 +29,13 @@ function exact_sum(P1::SparsePolynomialZonotope, P2::SparsePolynomialZonotope)
     return SparsePolynomialZonotope(c, G, GI, E, idx)
 end
 
+"""
+    ⊞(X::LazySet, Y::LazySet)
+
+Unicode alias constructor ⊕ (`oplus`) for the (concrete) `exact_sum` function.
+
+### Notes
+
+Write `\\boxplus[TAB]` to enter this symbol.
+"""
 const ⊞ = exact_sum