The Securities and Exchange Commission has not necessarily reviewed the information in this filing and has not determined if it is accurate and complete.
The reader should not assume that the information is accurate and complete.

UNITED STATES SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549
FORM 13F

FORM 13F INFORMATION TABLE
OMB APPROVAL
OMB Number: 3235-0006
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COLUMN 1 COLUMN 2 COLUMN 3 COLUMN 4 COLUMN 5 COLUMN 6 COLUMN 7 COLUMN 8
VALUE SHRS OR SH/ PUT/ INVESTMENT OTHER VOTING AUTHORITY
NAME OF ISSUER TITLE OF CLASS CUSIP (x$1000) PRN AMT PRN CALL DISCRETION MANAGER SOLE SHARED NONE
3M Co. COM 88579Y101 1,432 10,000 SH   SOLE   10,000 0 0
Altria Group Inc. COM 02209S103 841 20,048 SH   SOLE   20,048 0 0
American Homes 4 Rent Real Estate Investment Trust COM 02665T306 68,807 3,874,248 SH   SOLE   2,700,117 0 1,174,131
AmerisourceBergen Corp. COM 03073E105 149,043 2,051,241 SH   SOLE   2,020,778 0 30,463
Apple Inc. COM 037833100 194,993 2,105,416 SH   SOLE   2,084,045 0 21,371
Ares Capital Corp. COM 04010L103 68,961 3,861,184 SH   SOLE   2,526,013 0 1,335,171
Argo Group International Holdings Ltd. COM 002499543 3,865 75,630 SH   SOLE   73,343 0 2,287
Arthur J. Gallagher & Co. COM 363576109 70,735 1,517,922 SH   SOLE   988,999 0 528,923
Bank of Montreal COM 063671101 493 6,700 SH   SOLE   6,700 0 0
Bank of Nova Scotia COM 064149107 226,338 3,394,782 SH   SOLE   3,349,091 0 45,691
Baxter International Inc. COM 071813109 142,109 1,961,457 SH   SOLE   1,940,202 0 21,255
BB&T Corp. COM 054937107 250,363 6,358,881 SH   SOLE   6,295,320 0 63,561
Becton, Dickinson & Co. COM 075887109 112,446 950,518 SH   SOLE   936,240 0 14,278
Berkshire Hathaway Inc. CL A 084670108 51,653 272 SH   SOLE   270 0 2
Berkshire Hathaway Inc. CL B 084670702 6,509 51,428 SH   SOLE   43,281 0 8,147
Booz Allen Hamilton Holding Corp. COM 099502106 45,216 2,128,824 SH   SOLE   1,476,507 0 652,317
Brookfield Infrastructure Partners LP COM G16252101 19,815 474,798 SH   SOLE   424,297 0 50,501
Brown & Brown Inc. COM 115236101 50,915 1,657,928 SH   SOLE   1,069,695 0 588,233
Canadian Imperial Bank of Commerce COM 136069101 264 2,900 SH   SOLE   2,900 0 0
Canadian National Railway Co. COM 136375102 187,688 2,885,655 SH   SOLE   2,858,555 0 27,100
Canadian Natural Resources Ltd. COM 136385101 254,393 5,536,195 SH   SOLE   5,516,569 0 19,626
Canadian Pacific Railway Ltd. COM 13645T100 453 2,500 SH   SOLE   2,500 0 0
CARBO Ceramics Inc. COM 140781105 34,313 222,638 SH   SOLE   143,671 0 78,967
CBIZ Inc. COM 124805102 43,858 4,856,948 SH   SOLE   3,264,327 0 1,592,621
Celestica Inc. SUB VTG SH 15101Q108 145 11,500 SH   SOLE   11,500 0 0
Cenovus Energy Inc. COM 15135U109 243,057 7,497,657 SH   SOLE   7,472,207 0 25,450
CGI Group Inc. CL A 39945C109 340 9,600 SH   SOLE   9,600 0 0
Cisco Systems Inc. COM 17275R102 192,032 7,748,785 SH   SOLE   7,668,903 0 79,882
Coca-Cola Femsa S.A.B. de C.V. SPONSORED ADR 191241108 7,140 62,841 SH   SOLE   62,841 0 0
Copart Inc. COM 217204106 4,833 134,395 SH   SOLE   130,440 0 3,955
Corporate Executive Board Co. COM 21988R102 61,986 908,617 SH   SOLE   583,098 0 325,519
DeVry Education Group Inc. COM 251893103 91,186 2,153,666 SH   SOLE   1,413,659 0 740,007
Diageo PLC SPONSORED ADR 25243Q205 603 4,736 SH   SOLE   4,736 0 0
Dun & Bradstreet Corp. COM 26483E100 1,996 18,114 SH   SOLE   17,578 0 536
Eaton Vance Variable Rate Income Trust COM 278279104 10,228 677,790 SH   SOLE   677,790 0 0
Emerson Electric Co. COM 291011104 100,376 1,512,591 SH   SOLE   1,489,176 0 23,415
Enbridge Inc. COM 29250N105 494 10,421 SH   SOLE   10,421 0 0
EnCana Corp. COM 292505104 3,884 163,954 SH   SOLE   163,054 0 900
Entercom Communications Corp. CL A 293639100 6,655 620,241 SH   SOLE   620,241 0 0
Equifax Inc. COM 294429105 213,545 2,943,825 SH   SOLE   2,480,558 0 463,267
Expedia Inc. COM 30212P303 54,689 694,381 SH   SOLE   470,083 0 224,298
Expeditors International of Washington, Inc. COM 302130109 2,061 46,682 SH   SOLE   45,286 0 1,396
Federated Investors Inc. CL B 314211103 49,068 1,586,948 SH   SOLE   1,078,931 0 508,017
FirstService Corp. SUB VTG SH 33761N109 8,626 170,200 SH   SOLE   170,200 0 0
FXCM Inc. CL A 302693106 43,826 2,929,547 SH   SOLE   1,944,174 0 985,373
Generac Holdings Inc. COM 368736104 23,271 477,456 SH   SOLE   330,294 0 147,162
General Electric Co. COM 369604103 1,314 50,000 SH   SOLE   50,000 0 0
Gentex Corp. COM 371901109 129,736 4,459,816 SH   SOLE   3,463,315 0 996,501
GlaxoSmithKline PLC SPONSORED ADR 37733W105 742 13,878 SH   SOLE   13,878 0 0
Goldcorp Inc. COM 380956409 248 8,900 SH   SOLE   8,900 0 0
Google Inc. CL C 38259P706 18,213 31,660 SH   SOLE   31,170 0 490
Google Inc. CL A 38259P508 52,498 89,791 SH   SOLE   88,397 0 1,394
Graco Inc. COM 384109104 41,234 528,101 SH   SOLE   348,705 0 179,396
Harris Corp. COM 413875105 9,558 126,172 SH   SOLE   122,650 0 3,522
HCC Insurance Holdings Inc. COM 404132102 71,620 1,463,431 SH   SOLE   907,204 0 556,227
Hilltop Holdings Inc. COM 432748101 97,311 4,577,184 SH   SOLE   2,875,624 0 1,701,560
Humana Inc. COM 444859102 106,276 832,102 SH   SOLE   819,009 0 13,093
Jacobs Engineering Group Inc. COM 469814107 4,203 78,876 SH   SOLE   76,612 0 2,264
Johnson & Johnson COM 478160104 290,930 2,778,278 SH   SOLE   2,750,599 0 27,679
Kayne Anderson Energy Development Co. COM 48660Q102 30,682 896,092 SH   SOLE   575,309 0 320,783
Kraft Foods Group Inc. COM 50076Q106 899 15,000 SH   SOLE   15,000 0 0
Laboratory Corporation of America Holdings COM 50540R409 6,734 65,764 SH   SOLE   63,841 0 1,923
Leucadia National Corp. COM 527288104 151,336 5,771,768 SH   SOLE   4,949,466 0 822,302
LoJack Corp. COM 539451104 551 101,544 SH   SOLE   101,544 0 0
Lorillard Inc. COM 544147101 138,784 2,276,261 SH   SOLE   2,239,043 0 37,218
M&T Bank Corp. COM 55261F104 227 1,831 SH   SOLE   1,831 0 0
Madison Square Garden Co. COM 55826P100 43,751 700,579 SH   SOLE   480,878 0 219,701
Magna International Inc. COM 559222401 495 4,600 SH   SOLE   4,600 0 0
Manulife Financial Corp. COM 56501R106 404 20,300 SH   SOLE   20,300 0 0
MarketAxess Holdings Inc. COM 57060D108 83,770 1,549,581 SH   SOLE   926,130 0 623,451
McCormick & Co., Inc. COM 579780206 4,404 61,512 SH   SOLE   61,512 0 0
McDonald's Corp. COM 580135101 2,786 27,657 SH   SOLE   27,657 0 0
Merck & Co., Inc. COM 58933Y105 555 9,589 SH   SOLE   9,589 0 0
MICROS Systems Inc. COM 594901100 63,805 939,694 SH   SOLE   660,251 0 279,443
Microsoft Corp. COM 594918104 120,654 2,893,372 SH   SOLE   2,854,828 0 38,544
Mondelez International Inc. COM 609207105 564 15,000 SH   SOLE   15,000 0 0
Moody's Corp. COM 615369105 2,524 28,790 SH   SOLE   28,054 0 736
Morgan Stanley COM 617446448 956 29,571 SH   SOLE   29,571 0 0
MSCI Inc. COM 55354G100 77,095 1,681,468 SH   SOLE   1,135,596 0 545,872
Northern Trust Corp. COM 665859104 123,728 1,926,928 SH   SOLE   1,898,304 0 28,624
Nutraceutical International Corp. COM 67060Y101 24,618 1,031,765 SH   SOLE   651,804 0 379,961
Occidental Petroleum Corp. COM 674599105 230,613 2,250,515 SH   SOLE   2,228,745 0 21,770
Oracle Corp. COM 68389X105 226,400 5,585,557 SH   SOLE   5,525,505 0 60,052
Penske Auto Group Inc. COM 70959W103 105,940 2,140,197 SH   SOLE   1,382,760 0 757,437
PepsiCo Inc. COM 713448108 175,705 1,971,053 SH   SOLE   1,952,828 0 18,225
Pfizer Inc. COM 717081103 685 23,070 SH   SOLE   23,070 0 0
Philip Morris International Inc. COM 718172109 246,624 2,919,974 SH   SOLE   2,886,318 0 33,656
Potash Corporation of Saskatchewan Inc. COM 73755L107 287,323 7,554,849 SH   SOLE   7,463,549 0 91,300
Primerica Inc. COM 74164M108 90,754 1,896,640 SH   SOLE   1,275,999 0 620,641
Procter & Gamble Co. COM 742718109 85,473 1,087,575 SH   SOLE   1,071,999 0 15,576
Qualcomm Inc. COM 747525103 125,876 1,589,340 SH   SOLE   1,564,533 0 24,807
RE/MAX Holdings Inc. COM 75524W108 42,901 1,449,859 SH   SOLE   1,016,835 0 433,024
Ritchie Bros. Auctioneers Inc. COM 767744105 202,807 8,227,475 SH   SOLE   8,137,346 0 90,129
Rogers Communications Inc. CL B 775109200 99,302 2,467,531 SH   SOLE   2,435,691 0 31,840
Royal Bank of Canada COM 780087102 217,608 3,043,914 SH   SOLE   3,002,014 0 41,900
Shaw Communications Inc. CL B 82028K200 171,494 6,688,061 SH   SOLE   6,608,261 0 79,800
Solera Holdings Inc. COM 83421A104 3,567 53,119 SH   SOLE   53,119 0 0
SPDR S&P 500 ETF Trust TR UNIT 78462F103 4,697 24,000 SH   SOLE   24,000 0 0
SS&C Technologies Holdings Inc. COM 78467J100 66,251 1,498,210 SH   SOLE   1,023,396 0 474,814
Strayer Education Inc. COM 863236105 23,662 450,617 SH   SOLE   341,301 0 109,316
Suncor Energy Inc. COM 867224107 686 16,092 SH   SOLE   16,092 0 0
Synnex Corp. COM 87162W100 75,353 1,034,352 SH   SOLE   706,378 0 327,974
Talisman Energy Inc. COM 87425E103 235 22,200 SH   SOLE   22,200 0 0
Tech Data Corp. COM 878237106 52,371 837,674 SH   SOLE   479,675 0 357,999
Teleflex Inc. COM 879369106 57,143 541,126 SH   SOLE   360,788 0 180,338
TeleTech Holdings Inc. COM 879939106 4,601 158,701 SH   SOLE   153,912 0 4,789
The Babcock & Wilcox Co. COM 05615F102 68,735 2,117,540 SH   SOLE   2,078,112 0 39,428
Thomson Reuters Corp. COM 884903105 210,107 5,770,538 SH   SOLE   5,703,052 0 67,486
Tim Hortons Inc. COM 88706M103 3,588 65,589 SH   SOLE   65,307 0 282
Toronto-Dominion Bank COM 891160509 215,195 4,180,134 SH   SOLE   4,121,188 0 58,946
Tronox Ltd. CL A Q9235V101 33,799 1,256,456 SH   SOLE   1,133,722 0 122,734
U.S. Concrete Inc. COM 90333L201 449 18,161 SH   SOLE   18,161 0 0
Union Pacific Corp. COM 907818108 223,324 2,240,072 SH   SOLE   2,217,108 0 22,964
United Technologies Corp. COM 913017109 199,112 1,719,910 SH   SOLE   1,701,503 0 18,407
Valeant Pharmaceuticals International, Inc. COM 91911K102 493 3,900 SH   SOLE   3,900 0 0
Walgreen Co. COM 931422109 94,086 1,269,199 SH   SOLE   1,249,603 0 19,596
Wal-Mart Stores Inc. COM 931142103 1,126 15,000 SH   SOLE   15,000 0 0
White Mountains Insurance Group Ltd. COM G9618E107 5,862 9,635 SH   SOLE   9,352 0 283