diff --git a/NMSIS/doc/Makefile b/NMSIS/doc/Makefile
index ab3e4618e..0294c1dbb 100644
--- a/NMSIS/doc/Makefile
+++ b/NMSIS/doc/Makefile
@@ -8,6 +8,7 @@ SPHINXBUILD   ?= sphinx-build
 SOURCEDIR     = source
 BUILDDIR      = build
 DOXYDIR       = $(BUILDDIR)/html/doxygen
+# require NUCLEI_SDK_ROOT environment variable to be set to root of Nuclei SDK
 HTTPSERVER    ?= $(NUCLEI_SDK_ROOT)/tools/scripts/nsdk_cli/httpserver.py
 
 # Put it first so that "make" without argument is like "make help".
diff --git a/NMSIS/doc/source/appendix.rst b/NMSIS/doc/source/appendix.rst
index 043726653..e26c8c451 100644
--- a/NMSIS/doc/source/appendix.rst
+++ b/NMSIS/doc/source/appendix.rst
@@ -5,28 +5,41 @@ Appendix
 
 * **Nuclei Tools and Documents**: https://nucleisys.com/download.php
 
-* **Nuclei riscv-openocd Repo**: https://github.com/riscv-mcu/riscv-openocd
+* **Nuclei Software Opensource Organization**: https://github.com/Nuclei-Software
 
-* **Nuclei riscv-binutils-gdb**: https://github.com/riscv-mcu/riscv-binutils-gdb
+* **RISC-V MCU Opensource Organization**: https://github.com/riscv-mcu
 
-* **Nuclei riscv-gnu-toolchain**: https://github.com/riscv-mcu/riscv-gnu-toolchain
+* **Nuclei Toolchain Repo**: https://github.com/riscv-mcu/riscv-gnu-toolchain
 
-* **Nuclei riscv-newlib**: https://github.com/riscv-mcu/riscv-newlib
+* **Nuclei OpenOCD Repo**: https://github.com/riscv-mcu/riscv-openocd
 
-* **Nuclei riscv-gcc**: https://github.com/riscv-mcu/riscv-gcc
+* **Nuclei QEMU Repo**: https://github.com/riscv-mcu/qemu
 
 * **Nuclei SDK**: https://github.com/Nuclei-Software/nuclei-sdk
 
-* **NMSIS**: https://doc.nucleisys.com/nmsis/
-
-* **Nuclei Bumblebee Core Document**: https://github.com/nucleisys/Bumblebee_Core_Doc
+* **NMSIS**: https://github.com/Nuclei-Software/NMSIS
 
 * **Nuclei RISC-V IP Products**: https://www.nucleisys.com/product.php
 
 * **RISC-V MCU Community Website**: https://www.riscv-mcu.com/
 
-* **Nuclei Spec**: https://doc.nucleisys.com/nuclei_spec
+* **Nuclei RISC-V CPU Spec**: https://doc.nucleisys.com/nuclei_spec
+
+* **RISC-V ISA Specfications(Ratified)**: https://riscv.org/technical/specifications
+
+* **RISC-V Architecture Profiles**: https://github.com/riscv/riscv-profiles
+
+* **RISC-V Bitmanip(B) Extension Spec**: https://github.com/riscv/riscv-bitmanip
 
 * **RISC-V Packed SIMD(P) Extension Spec**: https://github.com/riscv/riscv-p-spec
 
+* **RISC-V Cryptography(K) Extension Spec**: https://github.com/riscv/riscv-crypto
+
 * **RISC-V Vector(V) Extension Spec**: https://github.com/riscv/riscv-v-spec
+
+* **RISC-V Vector Intrinsic API Spec**: https://github.com/riscv-non-isa/rvv-intrinsic-doc
+
+* **RISC-V ISA Extension Spec Status**: https://wiki.riscv.org/display/HOME/Specification+Status
+
+* **Nuclei Bumblebee Core Document**: https://github.com/nucleisys/Bumblebee_Core_Doc
+