Liquid formulations of urease inhibitors for fertilizers

A composition comprising:

• a) one or more urease inhibitors,
• b) a first solvent, and
• c) one or more solvents selected from the group consisting of:
• i) a second solvent, ii) a third solvent, and iii) combinations thereof,
• wherein said first solvent is one or more members selected from the group consisting of:
• i. dimethyl sulfoxide, and
• ii. one or more sulfoxide(s) of the structure:
• R9S(O)xR10
• wherein
• 1) R9 and R10 are each independently a C1-C6 alkylene group, an aryl group or C1-C3 alkylenearyl group, or
• R9 and R10 with the sulfur to which they are attached form a 4 to 8 membered ring wherein R9 and R10 together are a C1-C6 alkylene group which optionally contains one or more atoms selected from the group consisting of O, S, Se, Te, N, and Pin the ring, and
• 2) x=1
• wherein said second solvent comprises one or more aprotic solvents that are not identical to the first solvent,
• wherein said third solvent comprises one or more protic solvents,
• wherein said one or more urease inhibitors comprise one or more phosphoramides;
• and
• wherein said one or more urease inhibitors are dissolved in said first solvent in combination with said second solvent and/or said third solvent.