message: Updates source key
diff: @@ -22,7 +22,7 @@ This is completely uncalibrated, so it is not intended for instrumentation just
  ### Parts
  -| Item | Quantity | Manufacturer | Part number | Price (USD) | Sources | Notes |
  +| Item | Quantity | Manufacturer | Part # | Price (USD) | Sources | Notes |
  | ---- |---------:| --------------- | ------------------- | --------:|-----------------| ----- |
  | 1 | 1 | South Pacific | FlexLung | 129.00 / 5 | [Z][1amzn] | Test Lung or breathing bag or equivalent, many models out there, check eBay as well |
  | 2 | 1 | BXI or whatever | CA-BX-AP-PF | 28.95 | [Z][2amzn] | Just some sturdy material. Aluminum, wood, whatevery you have around. 1x 16x12 sheet needed, or 2x 8x12 sheets |
  @@ -30,7 +30,7 @@ This is completely uncalibrated, so it is not intended for instrumentation just
  | 4 | 1 | Alliance Rubber | 08997 SuperSize Bands | 7.00| [Z][4aamzn] | just some more big rubber bands. good for tuning the response. |
  | 5 | 1 | whoever | literally just some zip ties | 14.00| [Z][5amzn] | hopefully you have some zip ties at home already but if not, here's a link |
  | 6 | 1 | McMaster-Carr | 5463K615 | 12.00 for pack of 10| [C][6mcmc] | tee-juction to connect hoses to your test lung. Again sizes vary so this is just a suggestion. Find the right part for your hoses and your lung. Expect to use some tape to ensure a tight seal. |
  -| 7 | 1 | | | 6.98 | [Z][6amzn] | more rubber bands, optional or alternative to 3 and 3a |
  +| 7 | 1 | | | 6.98 | [Z][7amzn] | more rubber bands, optional or alternative to 3 and 3a |
  [1amzn]: https://www.amazon.com/FlexLung-Biomedical-Ventilator-Testing-Demonstration/dp/B07B876P9C
  [2amzn]: https://www.amazon.com/gp/product/B077Q2HYMW
  