You can obtain copies of these by joining the HIMALAYAN PLANT ASSOCIATION See: https://sites.google.com/a/shpa.org.uk/main/latest-situation

For further details of the association and its journals see:

plus the pages within the HIMALAYAN PLANT ASSOCIATION section within this web-site (scroll down the left-hand navigation bar - it is the sixth item, after 'Travel Advice in the Himalaya').