remove old chapter, update links

book/_toc.yml

@@ -397,9 +397,6 @@ parts:
       - file: external/learn-python/book/08/sympy
     - file: optimization/gurobi.md
       title: "Week 2.4: Gurobi installation"
-      sections:
-      - file: programming/gurobi/usage
-        title: Usage
 
   - caption: Fundamental Concepts
     numbered: 2

book/optimization/gurobi.md

@@ -6,11 +6,11 @@ title: Gurobi
 nav_exclude: true
 ---
 
-<!-- [deepnote.com](https://deepnote.com/){:target="_blank"} -->
+<!-- [deepnote.com](https://deepnote.com/) -->
 
 # Gurobi
 
-Gurobi is an optimizer written in Python. It's not open-source, but an academic license is available. This page shows how to activate the license. General instructions are available on [their support website](https://support.gurobi.com/hc/en-us/articles/14799677517585){:target="_blank"} as well, if additional information is needed.
+Gurobi is an optimizer written in Python. It's not open-source, but an academic license is available. This page shows how to activate the license. General instructions are available on [their support website](https://support.gurobi.com/hc/en-us/articles/14799677517585) as well, if additional information is needed.
 
 ## Before Starting
 
@@ -23,17 +23,17 @@ The software is easy to install, but keep in mind:
 <!-- {: .label } -->
 
 |**How to get a VPN connection with TU Delft IP Address**
-|The software eduVPN is described [here](https://www.tudelft.nl/en/student/ict/ict-facilities/virtual-private-network-vpn){:target="_blank"}. After reading the description, click on the "manual" button and select "Installing eduVPN for students," which will take you to the the [download page](https://tudelft.eduvpn.nl/portal/home){:target="_blank"}.
+|The software eduVPN is described [here](https://www.tudelft.nl/en/student/my-study-me/study-tools/remote-services). After reading the description, click on the "manual" button and select "Installing eduVPN for students," which will take you to the the [download page](https://tudelft.eduvpn.nl/portal/home).
 
 ## Installation Instructions
 
 Please do the following steps:
 1. Connect your computer to the TU Delft network by connecting to Eduroam or the TU Delft VPN.
-2. Register on the [Gurobi website](https://portal.gurobi.com/iam/register/){:target="_blank"} as a student. Set up your work as 'academic user', with 'student' as 'academic position'. You will be asked to verify your email address.
+2. Register on the [Gurobi website](https://portal.gurobi.com/iam/register/) as a student. Set up your work as 'academic user', with 'student' as 'academic position'. You will be asked to verify your email address.
 ![Register online](./images_gurobi/register2.png).
-3. Download and install Gurobi optimizer from the [download page](https://www.gurobi.com/downloads/gurobi-software/){:target="_blank"} for your operating system.
+3. Download and install Gurobi optimizer from the [download page](https://www.gurobi.com/downloads/gurobi-software/) for your operating system.
 3. If you are not on the TU Delft campus, this is when you should check to make sure your VPN connection is activated.
-4. Visit the [License Request section of your User Portal](https://portal.gurobi.com/iam/licenses/request){:target="_blank"}, find the "Named-User Academic" block and select "GENERATE NOW." Once accepting the agreement, you should be immediately able to copy the key, as shown in the image:
+4. Visit the [License Request section of your User Portal](https://portal.gurobi.com/iam/licenses/request), find the "Named-User Academic" block and select "GENERATE NOW." Once accepting the agreement, you should be immediately able to copy the key, as shown in the image:
 ![copy license](./images_gurobi/keycopy.png)
 5. We will open a command-line interface to set up the key (it doesn't matter which one you use, for example, the system default, Anaconda prompt or git bash; on **Windows** try `Win`+`R` then type `cmd` then press `enter`; on **Mac** open Terminal). For both platforms, all you should have to do is copy the license key, which will paste the following text: `grbgetkey xxxxxxxx`, where you should see your key instead of the `x`'s.
 6. Next, you should see a prompt that looks like this:
@@ -48,13 +48,13 @@ Please do the following steps:
     In which directory would you like to store the Gurobi license key file?
     [hit Enter to store it in LICENSE_PATH/gurobi]:
     ```
-7. You will be prompted to confirm the file location; it is strongly recommended that you accept the default location for your system by hitting `Enter`. If you need to store the license file somewhere other than the default location, please see [Where do I place the Gurobi license file (gurobi.lic)?](https://support.gurobi.com/hc/en-us/articles/360013417211){:target="_blank"} for important details. If successful, the following message will appear:
+7. You will be prompted to confirm the file location; it is strongly recommended that you accept the default location for your system by hitting `Enter`. If you need to store the license file somewhere other than the default location, please see [Where do I place the Gurobi license file (gurobi.lic)?](https://support.gurobi.com/hc/en-us/articles/360013417211) for important details. If successful, the following message will appear:
     ```
     info : License XXXXXX written to file LICENSE_PATH/gurobi.lic
     ```
-8. To test the installation, execute `gurobi` in your command-line interface and hit `enter`. Depending on your operating system configuration, you may need to try `gurobi.sh` or `gurobi.bat` as well. If this does not work, there are additional instructions [here](https://support.gurobi.com/hc/en-us/articles/13417565229713){:target="_blank"}, or you can also get help from an instructor.
+8. To test the installation, execute `gurobi` in your command-line interface and hit `enter`. Depending on your operating system configuration, you may need to try `gurobi.sh` or `gurobi.bat` as well. If this does not work, there are additional instructions [here](https://support.gurobi.com/hc/en-us/articles/13417565229713), or you can also get help from an instructor.
 9. Now you are ready to go!
 
-|If you need to find your license later, after it was generated, you can find it via the User Portal under "[Review your current licenses](https://portal.gurobi.com/iam/licenses/list){:target="_blank"}." Clicking the "Install" button, as shown below, will bring you to the same view as shown above in Step 4 to copy the license key. 
+|If you need to find your license later, after it was generated, you can find it via the User Portal under "[Review your current licenses](https://portal.gurobi.com/iam/licenses/list)." Clicking the "Install" button, as shown below, will bring you to the same view as shown above in Step 4 to copy the license key. 
 
 ![copy license](./images_gurobi/license.png)