['The', 'procedure', 'is', 'also', 'very', 'versatile', 'as', 'it', 'permits', 'meshes', 'with', 'different', 'distributions', 'of', 'y+', 'to', 'be', 'generated', 'with', 'ease', 'and', 'furthermore', ',', 'the', 'validity', 'of', 'these', 'meshes', 'is', 'guaranteed', 'if', 'the', 'initial', 'mesh', 'is', 'valid', 'and', 'the', 'polynomial', 'space', 'is', 'chosen', 'appropriately', '.']