Crossword clues for 20 sources 4 lettersAnswerClueATMS20 sourcesATOMSource of 20 AcrossRICESource of about 20% of the calories consumed by humanityBODYWith 20-Across, natural energy sourceCHARLESDICKENSSource of 20 AcrossTATERFolksy starch source found in 20-, 37- and 49-AcrossEURSource of about 20% of U.S. imports: Abbr.SONJAWith 71-Across, former skater/film star, and the source of the quote starting at 20-AcrossBILLYGOATReputed source of the 1-Across for 20-AcrossSILENTPARTNERBehind-the-scenes money source ... and a hint to the start of 20-, 35- and 43-AcrossEDGERSLawn trimming tools (Bonus diagonal clue: Extra power source, literally? [enter from this answer's 3rd letter to 20-Across' 4th letter])