Group by in LINQ

by

Let’s suppose if we have a class like:

class Person { 
    internal int PersonID; 
    internal string car; 
}

I have a list of this class: List<Person> persons;

And this list can have multiple instances with same PersonIDs, for example: 

persons[0] = new Person { PersonID = 1, car = "Ferrari" }; 
persons[1] = new Person { PersonID = 1, car = "BMW"     }; 
persons[2] = new Person { PersonID = 2, car = "Audi"    };

Is there a way I can group by PersonID and get the list of all the cars he has?

For example, the expected result would be 

class Result { 
   int PersonID;
   List<string> cars; 
}

So after grouping, I would get: 

results[0].PersonID = 1; 
List<string> cars = results[0].cars; 

result[1].PersonID = 2; 
List<string> cars = result[1].cars;

From what I have done so far: 

var results = from p in persons
              group p by p.PersonID into g
              select new { PersonID = g.Key, // this is where I am not sure what to do

Could someone please point me in the right direction?

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