diff --git a/PgpCore.Tests/PgpCore.Tests.csproj b/PgpCore.Tests/PgpCore.Tests.csproj
index 2a4ad9b..9162663 100644
--- a/PgpCore.Tests/PgpCore.Tests.csproj
+++ b/PgpCore.Tests/PgpCore.Tests.csproj
@@ -1,7 +1,7 @@
 <Project Sdk="Microsoft.NET.Sdk">
 
   <PropertyGroup>
-    <TargetFramework>netcoreapp3.1</TargetFramework>
+    <TargetFrameworks>net472;netcoreapp3.1</TargetFrameworks>
 
     <IsPackable>false</IsPackable>
   </PropertyGroup>
diff --git a/PgpCore.Tests/UnitTests/UnitTestsAsync.cs b/PgpCore.Tests/UnitTests/UnitTestsAsync.cs
index 4ecec59..0040a25 100644
--- a/PgpCore.Tests/UnitTests/UnitTestsAsync.cs
+++ b/PgpCore.Tests/UnitTests/UnitTestsAsync.cs
@@ -11,6 +11,17 @@ namespace PgpCore.Tests
 {
     public class UnitTestsAsync
     {
+        private static class File
+        {
+            public static FileStream Create(string path) => System.IO.File.Create(path);
+            public static bool Exists(string path) => System.IO.File.Exists(path);
+#if NETFRAMEWORK
+            public static Task<string> ReadAllTextAsync(string path) => Task.FromResult(System.IO.File.ReadAllText(path));
+#else
+            public static Task<string> ReadAllTextAsync(string path) => System.IO.File.ReadAllTextAsync(path);
+#endif
+        }
+
         [Fact]
         public async Task GenerateKeyAsync_CreatePublicPrivateKeyFiles()
         {
diff --git a/PgpCore/PgpCore.csproj b/PgpCore/PgpCore.csproj
index 6581f40..00fe141 100644
--- a/PgpCore/PgpCore.csproj
+++ b/PgpCore/PgpCore.csproj
@@ -1,8 +1,8 @@
 <Project Sdk="Microsoft.NET.Sdk">
 
   <PropertyGroup>
-    <TargetFrameworks>netstandard2.1;netcoreapp2.2;netcoreapp3.1</TargetFrameworks>
-    <Description>.NET Standard and Core class library for using PGP</Description>
+    <TargetFramework>netstandard2.0</TargetFramework>
+    <Description>.NET Standard class library for using PGP</Description>
     <Authors>mattosaurus</Authors>
     <Company />
     <Product>PgpCore</Product>
diff --git a/README.md b/README.md
index 669744d..013f142 100644
--- a/README.md
+++ b/README.md
@@ -4,7 +4,7 @@
 
 A .NET Core class library for using PGP.
 
-This is based on <a href="https://github.com/Cinchoo/ChoPGP" alt="ChoPGP">ChoPGP</a> but updated to .NET Core framework and to add in a missing utilities class.
+This is based on <a href="https://github.com/Cinchoo/ChoPGP" alt="ChoPGP">ChoPGP</a> but updated to .NET Standard and to add in a missing utilities class.
 
 # Installation
 To use PgpCore in your C# project, you can either download the PgpCore C# .NET libraries directly from the Github repository or, if you have the NuGet package manager installed, you can grab them automatically.
@@ -20,12 +20,10 @@ Add the following namespaces to use the library:
 using PgpCore;
 ```
 # Dependencies
-BouncyCastle.NetCore (>= 1.8.1.3)
-
-Microsoft.NETCore.App (>= 1.1.2)
+* Portable.BouncyCastle (>= 1.8.6.7)
 
 # Usage
-This is intended for usage in .NET Core projects, the latest version that works with .NET Framework is v2.2.0.
+This is intended for usage in projects [targeting .NET Standard 2.0](https://dotnet.microsoft.com/platform/dotnet-standard#versions).
 
 ## Methods