I am creating a page for a course, and I have the following file structure:

```
- content
- - teaching
- - - ml_algebra
- - - - index.md
- - - - class.md
- - - - ref.pdf
```

I have the following index.md

```
---
title: Fundamentals of Linear Algebra and Optimization for Machine Learning (2024)
subtitle:
# Summary for listings and search engines
summary:
# Link this post with a project
projects: []
# Date published
date: '2024-06-04T00:00:00Z'
# Date updated
lastmod: '2024-06-04T00:00:00Z'
# Is this an unpublished draft?
draft: false
# Show this page in the Featured widget?
featured: false
# Featured image
# Place an image named `featured.jpg/png` in this page's folder and customize its options here.
#image:
# caption: 'Image credit: [**Unsplash**](https://unsplash.com/photos/CpkOjOcXdUY)'
# focal_point: ''
# placement: 2
# preview_only: false
authors:
- admin
tags:
- Disciplines
- AI
- Machine Learning
---
This course equips students with the mathematical foundations of linear algebra and optimization, crucial for understanding and implementing machine learning algorithms.
```

And I want to link the class.md and ref.pdf at the end of this page.

this somehow styled page leaves a lot of possibilities where you did something wrong… and I don’t suppose you are *not* just asking how how to add a link in Markdown?`

please have a look at Requesting Help

To post code (that includes raw Markdown!), include it in three backticks like so:

```

`code goes here`

```

Please amend your original post accordingly so that we can see what you’re doing.

I’m sorry guys, now is it correct?

@irkode Yes, I’m using research group theme https://github.com/HugoBlox/theme-research-group

But in summary, I want to add a link in the markdown, but when I add the following codes by the end of my code

```
...
---
This course equips students with the mathematical foundations of linear algebra and optimization, crucial for understanding and implementing machine learning algorithms.
![PDF]({{< ref "/teaching/ml_algebra/ref.pdf" >}})
![PAGE]({{< ref "/teaching/ml_algebra/class" >}})
```

It results in the following errors:

```
ERROR [en] REF_NOT_FOUND: Ref "/teaching/ml_algebra/ref.pdf": "/home/marcos/Documents/Site/mraimundo/content/teaching/ml_algebra/index.md:63:8": page not found
ERROR [en] REF_NOT_FOUND: Ref "/teaching/ml_algebra/class.pdf": "/home/marcos/Documents/Site/mraimundo/content/teaching/ml_algebra/index.md:64:9": page not found
```

Thank you for the kind help.

you want a branch bundle

rename to `_index.html`

and assuming you want to link to the rendered version of the `class.md`

```
[PDF](ref.pdf)
[Class]({{% ref "class.md" %}})
```

- the leading ! is for including images you have none
- the ref shortcode is for pages
- always call it using % see Shortcodes | Hugo

at least that works with ootb hugo - your theme might behave different in that case you should contact the themes suport team.

Thanks!

I tried to use that, but it didn’t work. What worked was inserting the page in a folder.

```
- content
- - teaching
- - - _index.md
- - - ml_algebra
- - - - index.md
- - - - classes
- - - - - index.md
- - - - class.md
- - - - ref.pdf
```

Given that

```
[Class]({{% ref "classes" %}})
```

work, but

```
[Class]({{% ref "class.md" %}})
```

does not.

Also, by changing index.md to _index.md inside ml_algebra makes the page _index.md inside teaching does not work. Its content is the following:

```
---
# Leave the homepage title empty to use the site title
title:
date: 2024-06-20
type: landing
sections:
- block: collection
content:
title: Lastest Courses
text: ""
count: 3
depth: 1
filters:
folders:
- teaching
design:
view: compact
columns: '1'
- block: markdown
content:
title:
subtitle: ''
design:
columns: '1'
background:
image:
filename: ./ic_grad.jpeg
filters:
brightness: 1
parallax: false
size: full
text_color_light: true
spacing:
padding: ['20%', '0', '20%', '0']
---
```

Thanks for your help.

Glad u figured it out … told it may behave different with the theme