diff --git a/docs/src/api.md b/docs/src/api.md
index eedc304..25a5b12 100644
--- a/docs/src/api.md
+++ b/docs/src/api.md
@@ -2,6 +2,12 @@
 
 ## Portfolio analytics
 
+### Modules
+
+```@docs
+OnlinePortfolioAnalytics.OnlinePortfolioAnalytics
+```
+
 ### Asset return
 
 ```@docs
diff --git a/src/OnlinePortfolioAnalytics.jl b/src/OnlinePortfolioAnalytics.jl
index 6232cea..aa52d9b 100644
--- a/src/OnlinePortfolioAnalytics.jl
+++ b/src/OnlinePortfolioAnalytics.jl
@@ -1,4 +1,4 @@
-"""
+@doc """
 [`OnlinePortfolioAnalytics`](@ref) module aims to provide users with functionality for performing quantitative portfolio analytics via [online algorithms](https://en.wikipedia.org/wiki/Online_algorithm).
 
 [`EXPORTS`](@ref)
diff --git a/src/asset_return.jl b/src/asset_return.jl
index ce390da..2773623 100644
--- a/src/asset_return.jl
+++ b/src/asset_return.jl
@@ -1,4 +1,4 @@
-"""
+@doc """
     S
 """
 mutable struct SimpleAssetReturn{T} <: PortfolioAnalytics{T}
@@ -31,7 +31,7 @@ function OnlineStatsBase._fit!(stat::SimpleAssetReturn, data)
     end
 end
 
-"""
+@doc """
 The [`TYPEDEF`](@ref) abbreviation includes the type signature:
 
 $(TYPEDEF)