Condensed Statements of Cash Flows - USD ($)	9 Months Ended
	Oct. 31, 2016	Oct. 31, 2015
Operating activities
Royalties received	$ 3,910,855	$ 6,872,800
Interest received	3,819	4,953
Expenses paid	(953,926)	(888,880)
Net cash from operating activities	2,960,748	5,988,873
Investing activities
Maturities of U.S. Government securities	5,690,347	82,320
Purchases of U.S. Government securities		(82,628)
Net cash from (used for) investing activities	5,690,347	(308)
Financing activity
Distributions to unitholders	(5,904,005)	(8,921,606)
Net change in cash and cash equivalents	2,747,090	(2,933,041)
Cash and cash equivalents, beginning of year	2,587,165	8,717,943
Cash and cash equivalents, end of period	5,334,255	5,784,902
Reconciliation of net income to net cash from operating activities
Net income	5,198,145	5,825,977
Decrease (increase) in accrued income receivable	(2,078,052)	202,818
Increase in prepaid expense	(36,841)	(37,755)
Decrease in accrued expenses	(122,504)	(2,167)
Net cash from operating activities	2,960,748	$ 5,988,873
Non cash financing activity
Distributions declared and payable	$ 1,312,001