Regional tree-ring oxygen isotope deduced summer monsoon drought variability for Kumaun-Gharwal Himalaya - Santosh K. Shah; Max Berkelhammer; Qiang Li; Nivedita Mehrotra; Lamginsang Thomte; Richard Shell; Uttam Pandey; Narayan P. Gaire; Gayatri Kathayat; Ashish Sinha (Quaternary Science Reviews, 2023)