How to use foreach for JSON data in Blade in Laravel 5.8

Laravel newbie here! Below function retrieves all chapters of a book from a country specified as a slug (in Laravel 5.8):

$country = Country::where('slug', $slug)->first();
$results = $country->with('libraries.books.chapters')->get();

How can I retrieve all chapters from this output in Blade?

[{
    "id": 1,
    "created_at": "2019-09-13 22:41:18",
    "name": "USA",
    "libraries": [{
        "id": 626,
        "created_at": "2019-09-13 22:41:20",
        "name": "Stephen A. Schwarzman Library",
        "books": [{
            "id": 125,
            "title": "​​Manhattan Beach",
            "author": "Jennifer Egan",
            "created_at": "2019-09-13 22:41:20",
            "chapters": [{
                "id": 9413,
                "created_at": "2019-09-13 22:41:26",
                "nr": 1
            }, {
                "id": 9414,
                "created_at": "2019-09-13 22:41:26",
                "nr": 2
            }, {
                "id": 9415,
                "created_at": "2019-09-13 22:41:26",
                "nr": 3
            }, {
                "id": 9416,
                "created_at": "2019-09-13 22:41:26",
                "nr": 4
            }]
        }]
    }]
}]

This output is JSON (which I outputted using Blade , but I can't seem to find the right foreach syntax to retrieve all chapters. Below gives a syntax error on line 2 unexpected ')', expecting '[':

@foreach ($results->libraries as library)
    @foreach ($library->books as book)
        @foreach ($book->chapters as chapter)
            
        @endforeach
    @endforeach
@endforeach

Treating as an array results in the same syntax error:

@foreach ($results['libraries'] as library)
    @foreach ($library['books'] as book)
        @foreach ($book['chapters'] as chapter)
            
        @endforeach
    @endforeach
@endforeach

via Chebli Mohamed