diff --git a/content/_sec_intro.qmd b/content/_sec_intro.qmd
index 91521bf6..5b5ac9bd 100644
--- a/content/_sec_intro.qmd
+++ b/content/_sec_intro.qmd
@@ -32,10 +32,14 @@ For our circuit design, the most important parameters of the available devices a
 
 Xschem is an open-source schematic entry tool with emphasis on integrated circuits. For up-to-date information of the many features of Xschem and the basic operation of it please look at the available [online documentation](https://xschem.sourceforge.io/stefan/xschem_man/xschem_man.html). Usage of Xschem will be learned with the first few basic examples, essentially using a single MOSFET. The usage model of Xschem is that the schematic is hierarchically drawn, and the simulation and evaluation statements are contained in the schematics. Further, Xschem offers embedded graphing, which we will mostly use.
 
+A summary of important Xschem keyboard shortcuts is provided in @sec-xschem-cheatsheet.
+
 ## Circuit Simulation Using ngspice
 
 ngspice is an open-source circuit simulator with SPICE dependency [@Nagel_1975]. Besides the usual simulated types like `op` (operating point), `dc` (dc sweeps), `tran` (time-domain), or `ac` (small-signal frequency sweeps), ngspice offers a script-like control interface, where many different simulation controls and result evaluations can be done. For detailed information please refer to the latest [online manual](https://ngspice.sourceforge.io/docs/ngspice-43-manual.pdf).
 
+Important ngspice simulation commands and options (e.g., to control convergence settings) are listed in @sec-ngspice-cheatsheet.
+
 ## Integrated IC Design Environment (IIC-OSIC-TOOLS)
 
 In order to make use of the various required components (tools like Xschem and ngspice, PDKs like SG13G2) easier, we will use the **IIC-OSIC-TOOLS**. This is a pre-compiled Docker image which allows to do circuit design on a virtual machine on virtually any type of computing equipment (personal PC, Raspberry Pi, cloud server) on various operating systems (Windows, macOS, Linux). For further information like installed tools, how to setup a VM, etc. please look at [IIC-OSIC-TOOLS GitHub page](https://github.com/iic-jku/IIC-OSIC-TOOLS).
@@ -48,6 +52,8 @@ Experienced users can install this image on their personal computer, for JKU stu
 
 ::: {.callout-warning title="Linux"}
 In this course, we assume that students have a basic knowledge of Linux and how to operate it using the terminal. If you are not yet familiar with Linux (which is basically a must when doing integrated circuit design as many tools are only available on Linux), then please check out a Linux introductory course or tutorial online, there are many resources available.
+
+A summary of important Linux shell commands is provided in @sec-linux-cheatsheet.
 :::
 
 ## Setting up the Design Directory
diff --git a/index.qmd b/index.qmd
index 6f71d87b..a80d15f1 100644
--- a/index.qmd
+++ b/index.qmd
@@ -86,17 +86,17 @@ To be added in a future release.
 
 {{< include content/_app_voltage_buffer_zout.qmd >}}
 
-# Appendix: Linux Cheatsheet
+# Appendix: Linux Cheatsheet {#sec-linux-cheatsheet}
 
 {{< include content/_app_linux_cheatsheet.qmd >}}
 
-# Appendix: ngspice Cheatsheet
+# Appendix: Xschem Cheatsheet {#sec-xschem-cheatsheet}
 
-{{< include content/_app_ngspice_cheatsheet.qmd >}}
+{{< include content/_app_xschem_cheatsheet.qmd >}}
 
-# Appendix: Xschem Cheatsheet
+# Appendix: ngspice Cheatsheet {#sec-ngspice-cheatsheet}
 
-{{< include content/_app_xschem_cheatsheet.qmd >}}
+{{< include content/_app_ngspice_cheatsheet.qmd >}}
 
 # Appendix: Circuit Designer's Etiquette {#sec-designers-etiquette}