diff --git a/src/fixed.jl b/src/fixed.jl
index 6621e3c..e836fc9 100644
--- a/src/fixed.jl
+++ b/src/fixed.jl
@@ -45,7 +45,7 @@ Elements of [`SemisimpleBasis`](@ref).
 struct SemisimpleElement{P}
     elements::Vector{P}
 end
-SA.star(p::SemisimpleElement) = SemisimpleElement(SA.star.(p.polynomials))
+SA.star(p::SemisimpleElement) = SemisimpleElement(SA.star.(p.elements))
 
 function Base.getindex(b::SemisimpleBasis, i::Integer)
     return SemisimpleElement(getindex.(b.bases, i))
diff --git a/src/polynomial.jl b/src/polynomial.jl
index 4767dfb..879cfcf 100644
--- a/src/polynomial.jl
+++ b/src/polynomial.jl
@@ -41,6 +41,16 @@ end
 
 abstract type AbstractMonomialIndexed end
 
+"""
+    struct Polynomial{B<:AbstractMonomialIndexed,M<:MP.AbstractMonomial}
+        monomial::M
+        function Polynomial{B}(mono::MP.AbstractMonomial) where {B}
+            return new{B,typeof(mono)}(mono)
+        end
+    end
+
+Polynomial of basis `FullBasis{B,M}()` at index `monomial`.
+"""
 struct Polynomial{B<:AbstractMonomialIndexed,M<:MP.AbstractMonomial}
     monomial::M
     function Polynomial{B}(mono::MP.AbstractMonomial) where {B}