Proof positive : this chart tells how your most vital food is made safe : read what the figures mean / Co-operative Union Ltd.
- Co-operative Union Ltd.
- Date:
- [between 1930 and 1939?]
Licence: In copyright
Credit: Proof positive : this chart tells how your most vital food is made safe : read what the figures mean / Co-operative Union Ltd. Source: Wellcome Collection.
