diff --git a/docs/make.jl b/docs/make.jl
index b663201..afc3b91 100644
--- a/docs/make.jl
+++ b/docs/make.jl
@@ -11,6 +11,7 @@ using QEDbase
 
 #DocMeta.setdocmeta!(QEDbase, :DocTestSetup, :(using QEDbase); recursive=true)
 
+# TODO: remove before release
 Pkg.add(; url="https://github.com/QEDjl-project/QEDcore.jl", rev="dev")
 
 using DocumenterCitations
diff --git a/src/interfaces/process.jl b/src/interfaces/process.jl
index 5573037..f783de5 100644
--- a/src/interfaces/process.jl
+++ b/src/interfaces/process.jl
@@ -45,7 +45,7 @@ to enable the calculation of total probabilities and cross sections.
 """
 abstract type AbstractProcessDefinition end
 
-# broadcast every model as a scalar
+# broadcast every process as a scalar
 Broadcast.broadcastable(proc::AbstractProcessDefinition) = Ref(proc)
 
 """
diff --git a/src/particles/spin_pol.jl b/src/particles/spin_pol.jl
index 8b677cf..9695405 100644
--- a/src/particles/spin_pol.jl
+++ b/src/particles/spin_pol.jl
@@ -1,30 +1,30 @@
 """
-Abstract base type for the spin or polarization of [`is_fermion`](@ref) or [`is_boson`](@ref) particles, respectively.
+Abstract base type for the spin or polarization of particles with [`is_fermion`](@ref) or [`is_boson`](@ref), respectively.
 """
 abstract type AbstractSpinOrPolarization end
 Base.broadcastable(spin_or_pol::AbstractSpinOrPolarization) = Ref(spin_or_pol)
 
 """
-Abstract base type for the spin of [`is_fermion`](@ref) particles.
+Abstract base type for the spin of particles with [`is_fermion`](@ref).
 """
 abstract type AbstractSpin <: AbstractSpinOrPolarization end
 
 """
-Abstract base type for definite spins of [`is_fermion`](@ref) particles.
+Abstract base type for definite spins of particles with [`is_fermion`](@ref).
 
 Concrete types are [`SpinUp`](@ref) and [`SpinDown`](@ref).
 """
 abstract type AbstractDefiniteSpin <: AbstractSpin end
 
 """
-Abstract base type for indefinite spins of [`is_fermion`](@ref) particles.
+Abstract base type for indefinite spins of particles with [`is_fermion`](@ref).
 
 One concrete type is [`AllSpin`](@ref).
 """
 abstract type AbstractIndefiniteSpin <: AbstractSpin end
 
 """
-Concrete type indicating that an [`is_fermion`](@ref) particle has spin-up.
+Concrete type indicating that a particle with [`is_fermion`](@ref) has spin-up.
 
 ```jldoctest
 julia> using QEDbase
@@ -37,7 +37,7 @@ struct SpinUp <: AbstractDefiniteSpin end
 Base.show(io::IO, ::SpinUp) = print(io, "spin up")
 
 """
-Concrete type indicating that an [`is_fermion`](@ref) particle has spin-down.
+Concrete type indicating that a particle with [`is_fermion`](@ref) has spin-down.
 
 ```jldoctest
 julia> using QEDbase
@@ -77,19 +77,19 @@ _spin_index(::SpinUp) = 1
 _spin_index(::SpinDown) = 2
 
 """
-Abstract base type for the polarization of [`is_boson`](@ref) particles.
+Abstract base type for the polarization of particles with [`is_boson`](@ref).
 """
 abstract type AbstractPolarization <: AbstractSpinOrPolarization end
 
 """
-Abstract base type for definite polarizations of [`is_boson`](@ref) particles.
+Abstract base type for definite polarization of particles with [`is_boson`](@ref).
 
 Concrete types are [`PolarizationX`](@ref) and [`PolarizationY`](@ref).
 """
 abstract type AbstractDefinitePolarization <: AbstractPolarization end
 
 """
-Abstract base type for indefinite polarizations of [`is_boson`](@ref) particles.
+Abstract base type for indefinite polarization of particles with [`is_boson`](@ref).
 
 One concrete type is [`AllPolarization`](@ref).
 """
@@ -133,7 +133,7 @@ x-polarized
 !!! note "Coordinate axes"
 
     The notion of axes, e.g. ``x``- and ``y``-direction is just to distinguish two orthogonal polarization directions.
-    However, if the three-momentum of the [`is_boson`](@ref) particle is aligned to the ``z``-axis of a coordinate system, the polarization axes define the ``x``- or ``y``-axis, respectively.
+    However, if the three-momentum of the particle with [`is_boson`](@ref) is aligned to the ``z``-axis of a coordinate system, the polarization axes define the ``x``- or ``y``-axis, respectively.
 
 !!! info "Alias"
 
@@ -150,7 +150,7 @@ const PolX = PolarizationX
 Base.show(io::IO, ::PolX) = print(io, "x-polarized")
 
 """
-Concrete type which indicates, that an [`is_boson`](@ref) particle has polarization in ``y``-direction.
+Concrete type which indicates, that a particle with [`is_boson`](@ref) has polarization in ``y``-direction.
 
 ```jldoctest
 julia> using QEDbase
@@ -162,7 +162,7 @@ y-polarized
 !!! note "Coordinate axes"
 
     The notion of axes, e.g. ``x``- and ``y``-direction is just to distinguish two orthogonal polarization directions.
-    However, if the three-momentum of the [`is_boson`](@ref) particle is aligned to the ``z``-axis of a coordinate system, the polarization axes define the ``x``- or ``y``-axis, respectively.
+    However, if the three-momentum of the particle with [`is_boson`](@ref) is aligned to the ``z``-axis of a coordinate system, the polarization axes define the ``x``- or ``y``-axis, respectively.
 
 !!! info "Alias"