Sorting nested NSArrays with Objects - sorting

Hello you smart people out there. I need your help (again).
I have an NSArray that contains arrays of objects. Among the object's properties, one is called "name".
Each of the nested Arrays contains objects with the same 'name' (but different values for other properties). Simplified, it looks like this:
#[
#[myObject.name=#"c",myObject.name=#"c",myObject.name=#"c"],
#[myObject.name=#"a",myObject.name=#"a"],
#[myObject.name=#"b",myObject.name=#"b",myObject.name=#"b",myObject.name=#"b",myObject.name=#"b"]
]
Now, I want to sort my array, in such a way, that the nested arrays are in alphabetical order, like this:
#[
#[myObject.name=#"a",myObject.name=#"a"],
#[myObject.name=#"b",myObject.name=#"b",myObject.name=#"b",myObject.name=#"b",myObject.name=#"b"],
#[myObject.name=#"c",myObject.name=#"c",myObject.name=#"c"]
]
Does any of you have a hint on how to approach this? The nested arrays should not be sorted or rearranged internally.
Thanks for your advice

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