Implementing visitor pattern for a vector of objects in C++

This is a follow-up to this question.

We can implement the visitor pattern for the problem in the previous question, as suggested in this answer:

class Base {
    foo(Parent& p) {
        p.accept(*this);
    }
    virtual void visit(Child_A&) = 0;
    virtual void visit(Child_B&) = 0;
};

class Parent {
    virtual void accept(Base&) = 0;
};

class Child_A: Parent {
    void accept(Base& v) {
        v.visit(*this);
    }
};

class Child_B: Parent {
    void accept(Base& v) {
        v.visit(*this);
    }
};

class Derived_A: Base { 
    void treat_same(Parent&) {
        // ...
    }
    void visit(Child_A& a) {
        treat_same(a);
    }
    void visit(Child_B& b) {
        treat_same(b);
    }
};
class Derived_B: Base { 
    void visit(Child_A&) {
        // ...
    }
    void visit(Child_B&) {
        // ...
    }
};

But now consider if foo expects a std::vector< Base& > (or in the actual example std::vector< std::shared_ptr< fig::SpatialDifferencingScheme > >) as its argument. Then how can we implement visitor pattern for the problem? Is it possible?