[1a] Ber. 3, 223 (1870)

[1] D. R. P. 77,559; Frdl. 4, 34 (1894)

[2] D. R. P. 226,225; Frdl. 10, 167 (1910).

The method described above is a modification of a patented process,[3]

in which trinitrotoluene suspended in sulfuric acid is treated with chromic anhydride.

[3] D. R. P. 127,325; Frdl. 6, 148 (1901).