 There is a growing body of critical research exploring the attribution of Elizabeth's work to her husband.His own role in producing the lithographs has been questioned and examples of his style of drawing have been submitted to suggest that the actual drawing and coloring is likely the sole work of Elizabeth.Her role as sole artist of their first collection "A Century of Birds from the Himalaya Mountains" was acknowledged on every lithograph with the attribution "Drawn from Nature and on Stone by E.